They are alright, but you will end up replacing most of the stuff on them. I think they are great for little kids, but if you are going to use it a lot and want it to be capable, you would be better off starting with the regular AX10 and going from there.
We got my dad one for fathers day because he didn't want us to spend a bunch of money on one, it went about 5 minutes before the steering servo stripped out, luckily I had an old 645mg laying around that would work. The plastic steering links weren't far behind that. I spent about $50 on new shocks and replacing all the plastic suspension and steering links, now the ESC seems to be going out, reverse only works about half the time, and when it does work, it barely goes. The radio isn't anything special, you can get a Traxxas radio for $25 on E-bay that will be be better than this one. The stock motor isn't really a good crawling motor, even with the lower gearing it comes with, it still doesn't crawl very well, I ended up putting an old 55t Integy that I had laying around in it. So from what I have spent and what the used parts cost new, that is about $100 extra into it, and that isn't counting replacing the ESC that is on its way out.
Really the only thing decent are the axles, chassis plates, tranny, and beadlocks. They do come with straight shafts in the rear and a slipper clutch which are both nice pieces, but that is about it.
I started with a regular AX10, and the only thing I am using are the axles and tranny. If you want a good crawler, the best thing to do in my opinion would be to just get the axles and tranny for about $120, and go from there, then you can get whatever chassis, wheels, tires, and electronics you want, and you won't be wasting money buying stuff twice.