We use both the FT-12 (68 cal) and the FT-50 (.50 cal) markers as rentals. We add the clear GXG 200 round hoppers so we can see our players paintballs, an Exalt barrel sleeve (the guns also come with a cloth one that works fine). We power it with a Tippmann 48ci bottle. The only reason for the yellow bottle cover is so we can identify rentals from a distant easier. I find these guns to be very reliable. We wish the .50 cal was lighter than it is, but it still works fine for all ages. The current production runs have been trouble free for us; (We use these 2-3 time per week).