Hard to say right now, I'd like to see how this hammer prop does in the mud. IFFFF they last the same amount of time though i would go back to the GTR prop just because of the top end in the summer...

Honestly they both have their strengths.

I put a Hammer and a new big blade on my GTR today to give it a little comparison. The hammer and the big blade both ran almost exactly the same. All deep water speeds, going into current I could get 23.5 and going with the current I could get about 25.5 pretty steady.
I've got the heads decked .030 and everything ported and polished, carb is stock except a K&N air fliter, and exhaust is a BPS Q. Ran with about 700-800 lbs in my 1850 UncleJ.
With my stock prop that is showing a little bit of wear I'm getting 24.5 going into the current and a little over 26 going with the current.
I could have gotten better speeds if I would have found some shallow water but the river is really high right now and I didn't want to fart around too much.