I use the ND jetfin clone which is 35 quid delivered from Sports Components, I really like them. Not as big and solid as the original Scubapro one, but much more thrusty than most regular fins. plus, like the Scubapro one, they are big and black

If you want the extra push that the Scubapro gives, then its worth the extra money maybe for the original, but I find the ND clone more than adequate personally.