Thing I like about em is they are the basic kit, so any bells and whistles you want to add, you add them. You're not forced to buy someone else's idea of what they should or shouldn't have. And for the price they cannot be beat, and there I think lies a problem. From reading the forums on a couple of them, folks are thinking they are going to get something like a VQ P38 when they buy the Nitro version, and then complain about it. If they want that kind of quality and bells and whistles then they need to understand they have to spend the money for it, not bash a lower priced kit because it doesn't have it.
Me I have the Predator, the 52" and 90" P38's, and for the price I was more then happy with what I received. They are a basic kit, which in my case would have involved a long time if I was to attempt to build the same bird. But it was a foundation on which to build. In my case it was adapting them over to electric power, and on both of the 38's installing air retract systems. I got a good foundation for the price. What I built upon it was up to me and my budget.
My only complaint if I have one, is the manuals. Some more time should be spent on making them usable. Often I found some important steps missing and the explanations of how to do things a little lacking.