I've got some of these and it's made an amazing difference to my riding (I'm 6'6")
So thought I'd share when they put out this nice 1min vid that sums up in a minute the benefits of long cranks for tall riders.
Honestly - going back to my old bike with its 175mm cranks feels like riding a kids bike. (I now ride 210mm cranks)
If you're tall - my bet is that you'll watch this vid a few times...
Adrian.