I built a Hobby Boss AAV many years ago, no problems with it really.  I've seen some of their kits though, like the Leopard 2A4 or 2A6/7 that was lacking detail in some areas...  I'm all for accurate detail, but we all have to weigh kit vs price vs vs accuracy detailing to your own liking, etc... Also have to consider who their product is geared toward.  Some kits are intended for advanced builders, while others are aimed at novice or intermediates.