obviously you guys have not seen some of the dual xtm 24.7 thunder quake monsters over at extreme rc. those guys swear by the thunder quake and they build these things for a living. i have never seen a twin engine up close but i watched a couple of the videos and they rock. I have a single 24.7 in mine and it will hit up to 45 on the street. i have not broken one piece on it yet, the 2 speed tranny runs great and the reverse gear works like a charm. I think alot of you guys look at some of the older stuff duratrax made which quite honestly was trash and just take that opinion. The quality of their vehicles are comming up and mostly all they need is an engine upgrade because although the stock engines run really well they are under powered, as are most rtr's on the market. Plus in this hobby it is not so much what you buy, but how much work, love, attention, and lets face it, CASH, you can afford to put into your machine. My Advice is to buy a thunder quake. They are relatively inexpensive and run well to start with when you get an extra couple of bucks put a 24.7 xtm in it and you will be living good.
oh forgot to mention as far as no tunability. you hardly ever keep the same engine in a rc even when buying the most expensive, and the plastic parts (which are very few) are all garanteed for a year so as far as durability i don't think there is another company that matches that. there might be, i have not researched it but i don't think there is. just my 2cents