Some look better than others - even the stick on ones. It really depends on the type of car and frequency of driving in manual override as to whether they're appropriate.

On an S4/5 maybe, if you track it. The s-tronic box needs a lot more gear changes so longer paddles make sense as trying to change gear with the wheel rotated at all is a PITA!

The facelift S4/5 paddles from 2012 onwards are a good bit chunkier than the earlier ones, and can be retrofitted. They'd be worthwhile considering and I'm sure I've read a guide online of how to swap them.

Some I've seen look like a boomerang and are almost half the size of the wheel! They would defo look silly on an '8!