We took these two over to Whitby for the C2C
and brought them back from Whitehaven at the end, with no problems at all. I was suspicious at first, as I thought the binding wasn't going to be tight enough, but they were just fine. If you use the outer bottle bosses on the downtube, the grip might possibly interfere, but we had no trouble at all.
Strangely, Halfords gave the best deal when we bought ours - cheaper than most of the online dealers.