I'll probably get laughed at (by those that haven't auditioned them and those who believe the more money you spend the more you get audio-wise), but through extensive
auditioning of dozens of brands and models, from a couple of hundred per pair to $10K per pair, I was impressed by the audio similarity of the MA RS8's to the much cheaper JBL Studio S (S312) or Studio L Series (L890) speakers. Generally speaking, MA, B&W, and JBl offer very neutral and dynamic speakers with tons of mid and top-end clarity (without and harsh, sibilant highs). If you like the sound of one brand, IMHO you'll also enjoy the sounds of the other brands' equivalent models.
The savings in cash warrant your giving the JBLs a listen...especially if you're looking at an HT application.
As for dipoles, the room size and configuration could make some difference in performace of these vs. monopoles. It's a purely subjective decision you must make. My preference is for monopoles all around, but I have a large room and utilize a 7.2 setup. A small room and a 5.1 system may auger better for dipole surrounds.