For quite some time I have had a pair of Ergon GS1 grips on my Original Orange Brompton and they have served me pretty well. They are good grips but I have preferred the more rounded edges on the GP1 grips on my other Titanium Orange Brompton.
I have wanted a pair of the Biokork GP1's for some time but have not got round to buying them but I was recently able to get a pair at a great price.
The other trick is that cork has anti-bacterial and hypoallergenic qualities. I cannot say that this was the reason for me buying them but it's good to know.
I have seen these on one of David P's Brompton bicycles and always liked them. It is perhaps flippant to say I like the colour better than the black version as I feel it complements the Orange and Brooks saddle that bit more.
All in all I am rather pleased with them and in the little time that I have used them, for me they have been worth every penny.
At the moment I find I have a rather large soft spot for my Original Orange Brompton. There are a few more little enhancements I would like to make but it is the perfect commuting bicycle for me. I love my Titanium Orange Brompton, which is an S-type of course but my M-type really does feel like an old friend.