RE: Which cars/trucks would you NOT recommend, based on your experience?
Everything is wrong with ez start. I'd say the first thing is MORE BATTERIES to carry around, and also because it's totally unnecessary.
I'm going to defend the electric stampede. I build my own as a kit, back when it came with a manual speed control and the traxxas scorpion 20 turn. I put that truck through more abuse jumping it on concrete, smashing it into trees/poles/whatever and basically anything you would think would be destructive to an rc.. it took the abuse and asked for more.
But whatever you do, Don't go with any nitro duratrax rc, I have had a few duratrax rcs and I never had anything but problems, especially their nitro engines, i replaced my piston/sleeve way too many times. the engines were just so cheap they would break easily under normal use.