Yes, the 7's bring out more of the music's details--more space between instruments, parts stand out that I could not hear before. The presentation is quieter and more involving--more dimensional. The 7's are my first experience with monoblocks. I chose them over a pair of ARC VTM 200s. How do your Maggie's run with your 28BSSTs?
I went from the 4BSST(which also sounds great, but..). Much the same as you.. better soundstage and more lively presence
of sound, more involving. The volume level/quality of sound seemed to peak a little early for me with the 4B. The 28's definitely rock out better and stay nice and clean to volume levels everyone else in the house may or may not appreciate.
The one compromise with the Maggies, for me, was their limited impact, punch, volume capability, which I was aware of before buying. The 28's have solved that. I'm very happy with the combination.