I bought the Hogue rubber mono grip for my 6 shot .22lr SP101.
For me it's better than the stock model, I can get all three fingers on it.
But it has a 'round butt' shape to it that I don't care for. I feel like the muzzle droops down when I shoot round butt guns. I like a more square butt feel like the Hogue rubber GP100 grip.
They're also very soft and tacky, so they might not be the best for carry.