I have been wearing one of these for about 2 months; I really like it. I almost never even know it's there while I'm playing -- which, to me, means it's comfortable and I'm mobile.
I do not need a bigger shoe. I do need to lace a tiny bit looser on that side. My feet are narrow, so it isn't an issue. If you're already strained on the laces, though, it might be.