I honestly don't remember how long it took. I know it took a couple of tries, but when I went "all in" it didn't take long. My speed is still not fully up to where I was, but I haven't been trying to improve. Specifically, I got up to 70ish and then just stopped caring.

I'd hesitate to say I notice much of any difference. It makes me a little happy to have made the change. But, in the same way that moving a mouse to my off hand makes me happy. And is something I do every so often.