It all depends on the application.What type of rifle,ignition,etc.For traditional rifles stay with pure good ole fashioned black gold.(aka black powder).I don,t shoot inlines so I can,t give an opinion on those.
Goex is the main brand and is the most readily available.Call around the shops in your area,you should,t have trouble finding one that carries it.Heck,I even bought some from my local Gander Mtn.,so check yours.What rifle and cal is your rifle?
My buddy got some777 when he bought his first flintlock this year, and it has a bit of a delay in firing. I tried it in my gun, and the same thing. I gave him some FFF, and it pops right off like it should.