Tech2 vs Tech2win - Read before buying a Tech2 clone

It is very difficult here to find a mechanic that can interface with every function (diagnostic, coding, programming) and most don't know anything about the quirks and troubleshooting methods of these cars. Thats all good, all part of the fun of owning these cars out here they are very rare.
That leaves me with three options:
1) Tech2 clone - These use old hardware and GM have discontinued them although chinese companies seem to still be manufacturing them presumably because there is still a demand for them. There are mixed reviews on the internet but as a general rule it will work for what I need but maybe prone to failure. They will not interface with newer GM vehicles around 2010 plus? (might be slightly off on that year so don't quote me)
2) MDI clone - GM's diagnostic tool for dealerships is the MDI2. These are very expensive but can interface with every GM vehicle. The catch is that the software is done online and very expensive (around 2k per year for the comprehensive options or you can get a 3 day pass for around 50 bucks) The MDI was later replaced by the MDI2.
The chinese have copied the hardware for the MDI but not the MDI2. This probably doesn't matter for me. You can then obtain cracked versions of tech2win and GDS2 on the internet and use your clone MDI in order to interface with every tech2 function using the tech2win cracked version obtainable on the internet or in some cases included with the hardware. These are still somewhat expensive however theoretically more reliable and easier to transport provided you don't mind using a laptop. They are also much faster to transfer data when programming or retrieving data.
3) VXdiag Vcx NANO - This is basically a knock off MDI in a different case with a fake driver to 'trick' the GM applications (GDS2, Tech2win, TIS2000) into thinking its an MDI. These are very cheap and can be obtained for around $100. I have purchased one which includes the cracked versions of above programs.
Using the VXdiag NANO and tech2win application, I have been able to access every tech2 function including completing a CPS variation relearn, access all abs and airbag troubleshooting functions on my '99 C5 corvette. I have also been able to access ServiceProgramming System functions using TIS2000 and the vxdiag nano to update the PCM. This is very promising because of the price in comparison to a tech2 clone.
The catch? I don't think it will work on all GM vehicles. When attempting to interface with my '97 camaro, I was unable to access the ABS or airbag functions of the tech2, receiving a communications error. I guess my camaro is still old enough where the abs and airbag functions are performed over the OBD1 data bus (although it has an obd2 connector). However, I was able to carry out programming using the tis2000 application and access transmission and drivetrain functions.
If you are in the market for a tech2 for your C5 corvette, I think you should not purchase a tech2 clone. Instead, go for the MDI clone, or maybe the vxdiag nano if you are willing to risk the fact it seems to be hit or miss depending on the vehicle(s) you plan to interface with.
I have just purchased an MDI clone so will be interesting to see weather that will allow me to interface with the abs and airbagfunctions on my 97 f-body. If this also fails, I will have to purchase a tech2 clone.
One other thing to note, if you are intending to do programming, the TIS2000 application has not been updated by GM since 2008. Instead, they now use an alternative online based application called 'tis2web'. While TIS2web has been cracked for the european export GM vehicles, it has not yet been cracked for north american operation GM vehicles. As a result, if you are using a newer vehicle for programming, you will really need to purchase a 3 day subscription to tis2web.
Original:Tech2 vs Tech2win - Read before buying a Tech2 clone

Why do you need both GDS2 and Tech2Win for GM MDI?

Because GDS2 works for the new GM MY2010 only while Tech2Win works for the old.
Attach a chart: GDS2 vs. Tech2Win

Functions/ Software	GDS2	Tech2Win
Tool to work with	GM MDI	GM MDI
Diagnostics	Yes	Yes
ECU Programming	No. But you can log in www.acdelcotds.com to do programming	No. But you can log in www.acdelcotds.com to do programming
Key Programming	Yes. But you have to program new keys online via www.acdelcotds.com	Yes. But you have to program new keys online via www.acdelcotds.com
SPS Programming	No	Yes
Vehicle Coverage	Working for new GM motors 2010-	Working for old GM motors

Part 1: GDS2
In 2010, GM made a change in their vehicles moving to a Global platform to simplify marketing their vehicles all around the world.
The communication systems changed and the Tech 2 scan tool was no longer able to access them.
In preparation for this change, years earlier, GM had released a laptop based Multiple Diagnostic Interface or MDI . The blue box.
Note that the MDI 2 is used for reflashing only but the dealers loved it because it is twice as fast because of its USB connection to the laptop. (The Tech 2 is a Serial connection system and slower to transfer data for reflashing)
Back to the MDI. Global cars like the 2010 :
Chevrolet Camaro
Chevrolet Volt gas/electric hybrid
Buick Lacrosse
Cadillac SRX SUV
GMC Terrain
Chevrolet Equniox
We are now onto GDS2 which is simply a newer and better version than GDS1.
GDS2 requires renewing of the license to use it by visiting the Tis To WEB website at least once a month (if you have a yearly subscription).
Tis To Web as it is called is GM's website to download the scan tool or reflash data to update a vehicles computer.
You download vehicle software to your laptop and then you run the vehicle choice or program to scan from your laptop with the MDI 2 as the interface between your laptop and the vehicle.
You do not HAVE to be 'online' to use GDS2, only download the latest software license to use it by visiting Tis To Web monthly.
When you start GDS2, the bottom of the screen shows how many days left till an update is required.
If expired, simply log in to Tis to Web before you work on a GDS2 vehicle and renew your license then.
The above license requirements don't apply with a 2 day paid pass to use GDS2.
Part 2: Tech2win
GM also came out with a software program called Tech2Win.  (Tech 2 for Windows)
This is a Tech 2 emulator that runs on your laptop and simulates the Tech 2 screen and keypad to operate it.
Unfortunately, it leaves something to be desired with limited functions and some lack of actuator tests and incomplete coverage. It does not replace a Tech 2 and is a yearly subscription purchase but it is cheaper.
  Tech2Win also cannot be used for Saab or Izusu or Suzuki! 
GM really needs a laptop with a Intel I5 quad processor and 4 GIG of RAM plus Windows 7 Professional.
I recommend a refurbished Panasonic Toughbook CF19 tablet with 2.5 GHZ I5 quad processor with 4 partitions. You can use 1 terabyte solid state hard drives for speed and durability.
1 year warranty though you will probably never have a problem with one of these since they
are solid as a rock. If something were to go wrong after the warranty, I can get it repaired very cheaply. No sweat.
Keep GM by itself to prevent software conflicts and still get use of other operating systems to maximize laptop use with other software programs like Ford, Mazda etc.
When you first start up, the laptop pauses and offers you a screen with the 4 Windows operating systems. Pick which one you want and you are on your way. I also label them to make it more clear what is being chosen.
Example :
Windows 7 GM MDI 2
Windows 7
Windows 7
Windows 7
It's easy to name them anything you want.

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