Sebastien,

I've had the Mach 2 now for a several months and I too was very worried about portability.   My old mount was a Losmandy G11 that would split into two sections and that made the mount very light and manageable.  I live in a big city and I do not have the option of a permanent mount.  I'm very happy with the portability of the Mach 2.   I find it very comfortable.   I cradle the mount like a baby with both arms close to my chest and then set it on the tripod.   The weight of the mount on my digital scale is 44 lbs 5 oz.  That's with the polemaster camera attached and a DOVEDV10 saddle plate.  That's it.  No counterweight bar or weights attached.

Would I buy again?  Yes.  Absolutely and without hesitation.  The mount becomes invisible.