Personally I think it depends upon how handy you are and how much you like to tinker with things.
Myself, I prefer things that work right out of the box. I am not a willing tinkerer. (Is that even word?)
I've successfully used an couple of AGA-T2 RBAs. When they are working optimally, they've been the best vape I've experienced. However, they can be ornery, inconsistant, fussy, and unreliable. Mine seem to require constant tinkering. Did I say I don't like tinkering?
My two RBAs both need new coils, maybe new wicks, too. I haven't touched them for over a month because I'm lazy. Also because I know that I will have to devote half an hour to 45 minutes to do a total setup to complete both tanks to run optimally. In the meantime, my dependable and consistant cartotanks are keeping me more than happy.
So if you are like me, go with something less expensive initially and see how it works out. From what I understand, the better RBAs don't perform that much better than the less expensive ones do, it's more about the quality of the wick/coil which YOU make.