I have been wearing one of the old style under jersey air RXR V2 chest protector for the past 4-5 years.I usually wear a hard plastic over my jersey for the extra protection and for the shoulder protection.They are nice,a little warm at times but for the extra protection a will take it! A few months ago I got one of the new RXR Strongflex protectors,they give you more back/lower tail bone protection and are built with a heavier air bladder than the old style but the main thing I noticed was they are heavy to wear compared to the old style...Both of these chest protector are very nice and wouldn't ride without one!