I have an FX Impact M3 .25 Sniper I bought last year. I grabbed a bunch of JSB Exact King MkII Heavy pellets (34gr) and a Hill pump. It is sweet, and crazy accurate! Haven’t touched any of the adjustments - just pump and shoot!

I also bought some of the FX Hybrid slugs which are supposedly designed for the newer barrels included on the Impacts (and other FX rifles), but I haven’t tried ‘em yet.