The responses already made bring up excellent points. One thing I would point out is that the 3pt lift capacity will probably be close to DOUBLE the FEL lift capacity for most any small/medium tractor (most anything under 35 to 40hp) so if capacity it critical then the 3pt forks are the better choice.
If capacity is not the critical issue, but lift height is, then the clear choice is the FEL fork.
I have 3pt forks and for moving pallets around or for unloading pallets from a trailer they work great. I've run across many pallets (limestone slabs) where I could not lift them with the 3pt without unloading them part way by hand, so for me, FEL forks would never work because I lift pallets that are simply over the capacity of what the FEL could manage. I would suggest you seriously consider your needs. Let your needs make your choice.