HP 3 or standard valve

The HP3 valves have a second gauge so that you can read tank pressure without putting on a dead head and "better" valve knob. Not a dealbreaker for most, but you might want to consider ordering one of Joe Brancato's tanks instead at www.experthpa.com. His come with the dual gauges as an option and are made in the USA. Around the same price as you would spend on that omega tank.