If you have the chance to have a go on a high spec carbon bike then you certainly should go for it. They are amazing to ride at full chat and you can seriously tell where the development has gone. Moaning about locking one up in a dodgy place or having mudguards is missing the point by so much that point didn't even notice it happen. Having said all that I don't own one and and expensive one isnt on the to do list. But don't bash what what you haven't tried. Addendum , 3 years ago I had a go on a recumbent trike and I now own two, now that was a slippery slope !