I had an E-Revo 1.0 and I'm on my second Summit. (same platform)
After seeing what they did to improve the E-Revo, I would buy one in a second. They addressed all the weak points, except maybe the servos. That dual steering servo setup is stupid. No matter what you do, there will be a point where they are fighting each other and one will eventually strip or burn out. Then, the other one burns out shortly afterwards.

The differentials are greatly improved. It has the latch-on body with a ruggedized roof.

One important thing is to treat your batteries right, so if you do make an offer on the truck, consider the batteries a bonus. Make sure the seller insulates the battery terminals and pads them properly before shipping and declares them properly to the shipper. Or just tell him keep the batteries, mark the price down accordingly and you'll buy new ones.

Buy an extra set of suspension pushrods, as they're the first thing to go in a frontal collision with anything. Plan on a Savox steering servo in the near future. Other than that, you're all set.