While normally I'd agree with John on the descriptions of Wilson speakers as revealing, I don't believe that is as true with the Sophias that I have heard. They are much more forgiving of upstream components than the usual Wilson speakers (especially the Watt Puppy 7s you are going to hear).
Quite frankly, you can't go wrong with either of your choices, but I think you will lose a bit of the lowest bass you have in your current setup, since they don't have the bass extension of your subwoofer. However, an advantage of the floorstanders will probably be better integration of the bass they do put out, as you don't have to dial in a subwoofer to the proper crossover frequency, phase, etc. Listening to them both will probably let you know which speaker you prefer, but keep in mind that (1) the WP 7 you will listen to is a good deal more revealing and analytical than the Sophias and (2) it is likely that the SF speakers will not be optimally set up (I've never been a fan of the chain stores and their listening rooms). Both work very well with the ARC amplification you have. Good luck!