I have a great one and worth every penny I paid for it. It has two things important to me that make it so good. High quality glass lens and LED lighting (I hate fluorescent lights). Got mine from here
http://www.globalindustrial.com/p/office-school-supply/accessories-furnishings/desk-lamps/8-diopter-led-magnifying-lamp-with-covered-metal-arm-white
Least I'm pretty sure that is the one I purchased. It was a while ago. Great place to do business, I have purchased several things from them, never had any problems. I did receive a stool to sit on when sawing that was missing the ring that you rest your feet on. I called and ask if they would send me the part. No problem, they shipped it the same day priority mail, I had it in 2 days, not only the ring but the whole unit it was attached to, hydraulic tube and all. So I have extra spare parts now.
If you are not as old and blind as me and do not need a magnifying lens, ignore this post....