I prefer to go to vision express which is advised by my friend at first. The styles there are more than those in specsavers which I bought from before. Although the price is not as low as those in walmart, the eyeglasses in vision express are durable which can be worn as long as three years with little problems. If you want to save a little money, you can go to their online store.
Personally, i prefer to choose Specsavers because they provide both eye test and prescription eyeglasses. One of my friend have bout a pair at Specsavers. And their eyeglasses are looks nice and in good quality. Besides, it is not expensive of sunglasses there. And i have get an eye test at vision express for eyeglasses. I don't know why i got headache when i first wear it. So, i guess, maybe specsavers are better than vision express.