What are you planning to use it for? When I had my SR-22 i had a red dot on it, but realized it wasn't much fun that way. The SR-22 is too heavy to operate like an AR and move around with IMO, so a red dot is kind of pointless. Its much better on a bench or working off a tripod, which is why I'd rather go with a scope. Even something like a Millet 1-4x scope would be good, then you kinda get some of both worlds. But realistically a 2-7x or 3-9x would be just as good, so you can actually see the holes your shooting.
I would rather put a red dot on a stock 10/22 or one with a lightweight pistol grip stock, as it is much lighter this way and easier to handle than the heavy SR-22.