Wolf,
I put them all in Cubase SX, so swapping from channels was very quick/easy.

Comparing was easy as well :
#1 : Lowest soundlevel rating=7
#2 : lack of mid, sounds 'loudnessed' rating=6
#3 : Loudest level, lack of high rating=7
#4 : Too dark in sound rating=5
#5 : Nice clear sound rating=8
#6 : Bright, clear, warm sound rating=9 !

So, for me #6 wins

I like your voice Wolf.