Chiming in with another vote for PPP. I really like everything about it, except one. You can't wet sand it, the water will dissolve the putty. Other than that it's still my go-to.
My second choice is what Stik recommended, Tamiya. Hint: you can smooth it out with a q-tip slightly moistened with acetone.
I tried the Squadron putty a few years back. I can't qualify why, but I never cared for it.
Hope you like the PPP.