Ive owned the Manis and still own the Model 1s. I have no experience with the Ushers except some audition time with the 718s and other Usher models. To answer you question, in your size room the Bryston will drive the Manis (and Model 1s and 718s) quite well. IMO the Manis in such a small room may be a bit over powering. Id stick with the Model 1s and maybe add a small sub to give you a little more bottom end. Ive used a Velodyne DD 12 with my Model 1s with great success, and there are a number of subs that would mate up quite nicely with the Model 1s. Upgrading your source could definitely be a significant improvement. You might also want to consider tubes with the Model 1s. IMO it would be a big improvement over the Bryston, but then Im not a big fan of the Bryston sound.