I find that the turbohead with a skinny body of the M3T or M4 is a mismatch - it doesn't actually save me much space, or make it easier to carry. The M6 is my fave all the way - I actually sold off my 2.5" turbohead, as I found that I always choose either a standard Z3 or the M6 - if you've got those two, there's no reason on earth (for me, anyway) to have an M3T or M4.