I am using a stero pair of Sunfire Signature subs with my MG 3.5s. The blend is seamless. You need to move the subs away from room boundries and try to be easy on the volume control. In terms of scale, punch, dynamics and refinement the system approximates the performance of the ultra expensive full range systems.
Contrary to some opinions on these threads, properly positioned and configured sunfire subs are excellent complements to the Maggies. I am extremely happy with the results that I have obtained with the stereo subs.
Notes:
KEEP THE SUBS FROM ROOM BOUNDARIES. PLACE AWAY FROM WALLS, AND CORNERS!!!!
Remember that the controls are very sensitive, Minute changes in the phase and volume adjustment knobs make noticeable changes in the sound.
Use the lowest x-over setting (about 30Hz)
Use volume control no greater than 7-8 O'Clock
Adjust phase until the muddiness in the midbass disappears, and the air returns
Depending on room size, place subs on inside of panels (if room is narrow) or on ouside of panels (if room is sufficiently wide). You can experiment with placing the subs in the plane of the speaker
place the active woofer facing the listening position