Be sure to come back and post your thoughts.
Also be sure to use some quality recorded songs for your first round of listening if you can (unless of course you are just using the M3s for dvd movies). Many common, mainstrream music is recorded 'hot' (think of it as having the treble cranked all the way up) and this often makes good speakers sound harsh.
A ton of suggestions for quality recordings have been made on the forums already. Try out a search.

"Those who preach the myths of audio are ignorant of truth."