Yes because manufacturer claims are always true! Not!
Nope general consensus is that the V2 callipers are lighter than the M4’s. The tech M4’s with the braided hose are slightly heavier than the V2s with braided hose, the weight difference becomes appreciable when the M4’s are sold with the Race levers and non steel braided hose.
If you check Bikeradar the M4 races came to 460 grams with hardware and a 180mm rotor.
The V2’s came to 520 grams with a 180mm rotor.
Also see
http://singletrackworld.com/forum/topic/weight-of-the-hope-tech-brakes
and
the post near the end by dropadrop
http://forums.mtbr.com/brake-time/hope-tech-m4-v-v2-492778.html
If you are going to go with the Tech M4 you should just bite the bullet and go with he Tech V2 and swap out the practically useless steel braided hose to partly make up for the increased rotating weight of the rotors.