Spoken to one of the raptors about ATS markers, and apparently they are a bugger to get working correctly, but once they are working they are awesome, I think they are basically and 'autococker' based mechanism with as canon fodder said an elegant mag design. So long as the bolt action isn't like a tiberius I can't see much going wrong with them once you get it working right. Mag fed markers are just too damned expensive unless you use them all the time, my tib T9 spends most of it's time in the cupboard or as a pistol for CQB stuff (probably once/twice a year). Tac caps on any cyclone/ripclip equipped marker is much more popular. Although got to admit the most fun I've had was holding off a group of players with my pistol, two mags and a pod of first strikes, to this day I'm not sure how I managed to get away with it but it was freaking awesome