My CFX hates anything Crosman, come to think of it, so does my 350. So maybe it's just me :-)! Regarding the Exacts, look on the back of the tin. All of mine have a small sticker, looks like some kind of stock number, but if you look close, you'll see 4.50, 4.51, etc. My rifle definitely gets the best accuracy and velocity with 4.52's, 4.53's are almost as good, but a little slower, the others just plain suck. Interestingly enough, a freind of mine has a S1K that has the exact same preference in pellets. Shoots almost the same, too. 2nd best pellet in mine is probably the RWS Superdomes. Good luck.
Dave