IMO if you have less than a 33inch waist, even the v7 P1 strippers for all of their modification with the Velcro, you are going to have them sliding down. You just can't get them tight enough with the way the 2 halves of Velcro align, and if you do (a) it's such a small contact that they come undone, or (b) the two ends of the 'belt' sag in the middle over your crotch and becomes uncomfortable, the whole thing liable to slipping, and frankly messy.
Also, to get a tight fit on the front thigh guard on is not possible on a thigh of average proportion for a 31-32inch waist, and trying to do so just causes the elastic to give out at the seams within a few hours usage.
I've gone back to P2's but still haven't found the ultimate solution to protection, comfort and maneuverability.