I have the MCA-2 and consider it a decent enough amp. But I think you will find the MCA's to be a bit dark and would match if carefully to your speakers. I do not know the sound of Def Tech speakers and so cannot comment on how they would work together but I have B&W CDM 7SE's along with a Sonic Frontiers Line-1 Preamp and am relatively happy with the sound, although the Bryston sounded cleaner when I compared it against the Anthem at time of purchase.
Have you considered the Bryston 9B-ST five channel amp, I don't know what your budget is but the Bryston is about double the cost of the MCA.
Have you considered the Bryston 9B-ST five channel amp, I don't know what your budget is but the Bryston is about double the cost of the MCA.