Larryb
I've had mine for about two years and it's the best purchase I've ever made. It gives me more energy, actually makes me look and feel younger, helps me snap back from intense physical activity almost immediately, lowers my blood pressure.
I use and have used colon cleanses, oil pulling, goji berries, all kinds of pricey supplements. While all of these things have benefits that are obvious to me (I've tried many other things that had no effect), the Qlink has made a more profound change than any, and I wouldn't be without mine. Considering I paid $80 two years and I'll feel the results every day forever, it's been a heck of an investment.
As one poster mentioned, I'll get a bit amped out sometimes too and need to take it off. But if I misplace it for a couple hours it drives me up the wall and I end up pulling the place apart looking for it. Recently I swapped my 3.0 Qlink for the original that my friend was wearing. I wanted to see if I felt less amped with the original. After 5 days my friend almost refused to trade back, and after putting on mine again it was like a breath of fresh air - the other one was too weak for me.
I'll probably go to sleeping with mine off for awhile. It's always nice anyway to put it on first thing in the morning and have that big energy boost to start the day.