I've owned the Bryston 7B monos and personally did not find them bright sounding driving Thiels. When the upgrade bug hit I auditioned the ML336 in my system at length. The ML336 is more refined and detailed sounding across the range, the soundstage is much larger and better defined, and the bass is deeper and more controlled. On the flip side the ML336 is darker sounding, the mids are more recessed, and overall it is a more reserved sounding amp. On large scale symphony the ML336 sounded great, on rock I found the bass to be strong and controlled, but a bit sluggish. If at all possible you should audition the two amps in your system. I ended up with a large Classe amp which gave me the additional refinement I was looking for, and imo has a more lively and open character then the ML336.