In my system (Gallo Ref 3 speakers and a VSE level 4 Sony DVP-9000ES), I've had a PS Audio GCC-250, a Sim Audio I3, an Underwood Hifi-modded Musical Fidelity A5, and the NAD M3. Of all of them, the NAD M3 was my favorite in most respects, except that I found a certain "closed-in" quality on the top-end and occasional rhythmic sluggishness that I just couldn't get over. I tried swapping in better jumpers, using power conditioning (an Audience AR1p), but I just couldn't get those qualities to go away, particularly the closed-in top end (an issue which I believe a few forum members have also commented on).
I ended up going with the MF A5, which has a more extended top end and better channel separation, but does not have the same palpable immediacy that the M3 had, nor its seemingly endless bass reserves. Despite the posted power ratings, the M3 struck me as being a much more powerful amplifier than the A5, and if it hadn't been for those deal-breaking quirks (which may well have been entirely unique to my system), I would have kept the M3. Either way, I definitely preferred both the M3 and the A5 to the PS Audio unit or the Sim I3.
I ended up going with the MF A5, which has a more extended top end and better channel separation, but does not have the same palpable immediacy that the M3 had, nor its seemingly endless bass reserves. Despite the posted power ratings, the M3 struck me as being a much more powerful amplifier than the A5, and if it hadn't been for those deal-breaking quirks (which may well have been entirely unique to my system), I would have kept the M3. Either way, I definitely preferred both the M3 and the A5 to the PS Audio unit or the Sim I3.