just to add something else to consider:
this question depends on what you're going to do long-term. if you ever decide to go the 24v route then a 2.8i will save you a lot of trouble, as wil it if you go YB.
If you're looking to go fully tuned pinto flavour or zetec, then the normal 4 pot stuff is ideal.
whichever you choose, good luck with it