Maggies aren't a reactive load, they're almost purely resistive and a flat 4 ohms across the band, and in that sense shouldn't cause any amp to be unstable (as in oscillation). But if you mean will the amp clip at too low a volume, Maggies are low sensitivity and can require a beefy amp to play loudly without clipping, especially in a large room. So it depends on the particular combo of Maggie model, amp, room size, and what you as the listener consider to be adequate volume with your program material. But the speakers are fairly indestructable, so if you begin to hear distortion/compresssion as you turn it up, just back off a bit and that's your speed limit. If it's not high enough for you, you probably need a more powerful amp, but I doubt you'll harm anything in the process of finding out.
