I've always loved the 5a, in fact, I had a pair for about 4 months and loved them. I didn't have the correct upstream gear with them though, ARC is a classic choice.
I have heard the 7's several times, including in the Vandersteen room at CES when they first came out. I think they are better than the 5's, by about 2%, and they cost about 300% more, so.....
Don't sell them, or if you do, contact me and maybe I will try them again!!