Proline Slingshots vs Sandpaws
 

I don't see the difference here except that one is meant for a sct. Which has better more traction on loose surfaces like sand and dirt? Does the tread design make a big difference on the sandpaws?

Re: Proline Slingshots vs Sandpaws
 

The Slingshots look cool, but they're possibly the worst performing rc paddle available. The Sandpaws are great, I'm more of a fan of them in 2.8" since the 2.2"s are kinda short and tend to dig in deep enough to beach my axles (or chassis, depending on the car they're mounted to) more frequently, more so on 2wd's. Even the shorter Sandpaws are wider and have deeper tread than the Slingshots. In fact, the only paddles I've run that had deeper scoops than my 2.8" sandpaws are the huge Duratrax paddles on my 1/5 scale. The offset lugs of the sandpaw are a little more resistant to getting shredded than a straight blade if you find yourself running on hardpack/gravel.

What vehicle are you wanting to put them on, and do you have a size preference?

Panther paddles work very well too, and believe it or not, Traxxas paddles might be even better.