Dude used vastly different tire sizes on a 4wd... I wouldn't buy a brick off him.
That's a v1 (possibly v2?), with crap servo and self-igniting ESC.
Stay away.
It's not that good of a deal to risk it. I used to bash my v3 Kraton with a buddy that had an e revo, IMO they're close enough where you won't be getting an upgrade. Different things break on them, but they do break.