The last time that I checked with Snap-On, their "big" diagnostic instruments such as their Modis or Solus Systems did little more than read OBD II codes on Vipers...as the market was/is so small, Snap-On did not want to pay D-C (it was about 1.5 years ago that I last checked) for the ability to add Viper to their list of program "keys" that are needed for each manufacturer. It did work well on 1998 Grand Cherokee, but couldn't even identify the 2006 Jeep Commander (CAN bus). Needless to say, I "passed" on the $7000.00+ Modis system.
I was told by Mr. Tom Sessions that the 2008 Viper was a "mix"...SO, I plugged my DRB III into our 2008 Coupe and was happy to see that I could read/do many (though not all) things that I wanted to see...at least for tonight.
Looks like I'll be "needing" a StarMobile" in the near future!!