My wife bought me one of the early Black Rapid RS-7 straps about 5 years or so ago and I have sworn by it ever since - carries the 1D mk4 with 300 2.8 all day long without a problem. It had an early version of the 'locking' clasp on the strap which occasionally got stuck and took a fair bit of 'persuasion' to unlock it. Well I decided to order a replacement and contacted Black Rapid only to get an email back saying how sorry they were about the issues I had, and that it was a very early design / part - could I supply them with my address as they would like to send me a replacement 'new version' strap.
To say I am surprised as well as impressed is an understatement, I will continue to praise and support the company as I have always done - and people wonder why sometimes paying that little bit more for an original product rather than a cheaper 'copy' is the way to go.
So a HUGE thumbs up to Black Rapid from me!!!