If you specialize on BMW and Benz, then it will be good to invest in the ELITE to have access to the programming software.
Remember 98% of programming is done with a laptop and the j2534 ( you dont use the tablet)
If programming on these 2 manufactures is not important..
Then you can get the IM608.
If you need bmw and benz programming programming then get the Elite and also the IM508.
Elite does Mercedes and bmw programming
IM608 does keys. Not the programming
Other than that it’s the same diagnostic software
Buying guide: IM508 or IM608?
I love the im508 if I didn’t have the elite I might of bought the 608 but I can do more with the Maxisys elite and im508.
The adapter is for Benz and it looks like a Benz key and it connects to the scanner. You can also buy nust the xp400 adapter if you really want to do cas4 bmw too. The software from the 508&608 are identical. No difference at all.
(Thanks to Mr. Welding for his advice)