My choice would be the rip-claw design because of its straight claw. If I’m sliding down the roof – something more likely if the roof pitch is greater than 8/12 – I want a hammer that I could bury into and through the sheathing, shingles and all. A curved-claw hammer has the potential to glance off the roof. If that happened, I’d find myself face down in the dirt. Not a good thing.