They are and they are not. I've used jubilee clips without issue although unless you get something that's a tight fit when fully open over the pipe they tend to squash / pinch it and go slightly oval.
The crimp type clips are slightly better, but with care jubilee are OK, just ensure you have a decent selection of small ones, as you really do not want to wind them up too much for ovality reasons.
Note: You can get air ingress with no leakage of fuel as its slightly under suction pressure anyway (sort of) , so makes sense to get clips that are a reasonably tight fit to push along the pipe when fully open, then you only need to tighten them a little bit too.
Andy.
91 205D-Turbo, gone but still missed
02 106D, TUD5B, gone but not really missed apart from the MPG
I would agree with andy, I only use Jubilee type clips but do use the correct size, if they are to large they cause a flat on one side. For low pressure applications cable ties work very well.