ARF's are KING!!!!
I covered a RadioCraft for a friend - I don't think I can do work that well and I've built about 30 planes in the past 3 years.
The only problem I saw was that the control surfaces weren't scale sized, so doing a covering job involved a lot of guestimation about where to put the accents.
However, I'd consider this more of an ARC than an ARF in that there is a couple of weeks of evenings involved just getting it ready for the hardware.
Would I like one? Well, not my cup of tea, but certainly made me more aware of how precise things can be.