They are damn good cars for the price, easily comparable to the RC18T. 

Only complaint is the spur gear and pinion gear are not covered. Not really a problem though if you dont go offroad that much. I would recommend making one though as dust and sand wear down gears really quickly. 

They have full bearings throughout and adjustable tie rod ends and struts. Alum dog bones also. 

Adjustable ball diffs front and rear with plastic gears, recommend to regrease them from new. Diff balls are good if you don't overtighten them.

I have got ezrun 25a brushless esc's and ezrun 5200kv 18t motors. I have put 10t pinions also as they way too fast. Any faster motor is just overkill. Mine easily do 50kph with the current set up and that is fast enough. I'm only using 2s 7.4v lipo's also, they are more than enough power. I have bashed the hell out of mine and have only broken the shock towers which I replaced with alum ones, haven't broken anything else since. 

One good thing is that many of the parts are directly compatible with the Associated RC18T, Parts such as, diff internals, wheel hubs, tie rod ends, shock towers, wheel axles, bearings, wheels, shocks, front and rear arms and I presume dog bones (but haven't actually tested them). The diff housings may also be compatible although I haven't tested this.

I would recommend one to anyone if they want a tough buggy with all of the features normally found in cars twice the price. 

Oh and put some bumper bars on them if you plan to do a lot of bashing.