I love mine. I had it fitted at Burghley a couple of years ago. I like the fact it moves with you when you breathe as I'm an asthmatic so catching my breath xc is a challenge without a restrictive BP
Have a Kan and totally love it. It does feel bulky to carry around but when it's on it's absolutely fine. Used to ride my old horse in it, hacking and jumping , and I can honestly say it works very well as a BP. Had my worst ever fall while wearing it (and an HS1 skull) - wont go into detail but it was a really bad crash at galloping speed - and i think it saved my life.
Needs to be properly fitted but once on I'd never wear anything else.
PS? Should say have now sold the horse and bought a much safer highland so don't feel the need for it so much now tbh.