So far, I've killed 3 bosses and my saw cleaver is +3.

I have tried Kirkhammer. It's good and all but it's a little bit slower than saw cleaver so I'm not really digging it.

What is a good replacement for saw cleaver? Can anyone give me a suggestion?

Personally I really like the Hunters Ax. It's just as fast as the saw blade but it does a bit more damage then the saw cleaver at +3. When you transform the ax it gains more range and the first light attack is a horizontal swipe that is good for hitting multiple enemies at once.

Ludwig's Holy Blade is still doing it for me. It's as fast as the Saw Cleaver roughly, unless you change modes in which case it is a greatsword powerhouse. But not that much slower than the Saw Cleaver's second mode. And it does tons of damage, even on my Skill build.

@nohthink: I started with the saw cleaver and the only weapon i've been happy with since is Ludwig's Holy Blade. It's still slower, but once you get the hang of it it's a great weapon.

I like the Threaded Cane. It's slightly slower, but I much prefer the whip form's reach and crowd control to the saw cleaver's alternate.

I beat the game with the saw cleaver, I think it's amazing in it's non-transformed staged because of how fast it is. Truth be told I didn't try all the different weapons though, just some of the, and the ones I tried I liked less than the saw cleaver.