Frankly, what can you expect for $2.46? That light looks really cheap to me, about the kind of junk (for lack of a better word) sold at the dollar store.

If you are specifically looking for a slim 1xAAA light, there are no doubt many better choices available. Maybe something along those lines:

http://www.nitecore.com/productDetail.aspx?id=27
http://www.nitecore.com/productDetail.aspx?id=26#.VMqXcy48qao

Either would meet your expectations (0.49" dia.). Not terribly expensive but a whole lot more dependable than the no-name $0.99 wonder light from eBay.