I've only used the vibrating ones, Shag Factory Day Tripper and a 3 pack 'Grab Bag'. Out of those I prefer the Day Tripper, it's much thicker and therefore tighter on your shaft. I haven't used any 'normal' cock rings but have used the vibrating one with vibrations turned off and they're just as good.
They did keep me harder for longer, obviously, and the vibrations are great for both of you. They're definitely something I'd reccomend to you if you want to go for longer or just add something to sex.
No experience with the China Brush Delay, sorry.