i dont know if this is the right place(sorry mods) but i bought one of these(purely for my automag) and it is awsome i fired roughly a bag of cheap site paint and not smegged any balls apart from the last ball. if you have a tourny marker with alot of kick this is awsome i used it on system-x (timmie copy) and it kept up with the 10.5 bps i would reccommend this as a back up hopper!!!
http://cgi.ebay.co.uk/Tacamo-200-round-Arc-Hopper-Paintball-/270621145774?pt=UK_Sporting_Goods_Paintballing
http://cgi.ebay.co.uk/Tacamo-200-round-Arc-Hopper-Paintball-/270621145774?pt=UK_Sporting_Goods_Paintballing