I got a pair of prescription sunglasses from one of the cheap internet eyeglass places, goggles4u, and I am very impressed. My prescription is pretty high and weird, so glasses are expensive to start with, and sunglasses have always been too much of a splurge. $250+ or so. But these only cost $38, so why not? I ordered on July 21 and got them today, so that's not a bad turnaround either.
In retrospect, I probably should have gotten plastic frames that felt more like a sunglass frame. These are just normal glasses tinted. Oh well, no big deal to buy another pair.