From what I heard I would say stay away. I thought about getting them at one time, but most people say they malfunction and sometimes just straight go out and don't work at all. Maybe they've fixed it by now, it was a year or soo ago.
I got GlowShift as an alternative to Cyberdyne and can't be any happier about them. I figured for the price they were worth a try. Alot of colors and the deal sealer for me -- they offer a digital nitrous pressure gauge.