From my experience, it comes entirely down to player knowledge. We just wrapped up a PF campaign at 8th level, and I was playing a ranger. Between my multiple attacks at different attack bonuses, miscellaneous buffs from the bard and cleric, and other floating modifiers, my turn took much longer than it does in our 4e campaign.
If people know what they're doing, combat can absolutely fly. With more of the players familiar with 4e, our combats are sometimes half of what they were in PF. In PF, the casters wouldn't help fight in the first couple rounds because they had to buff, and when they did, my ranger's damage completely outstripped theirs. Sure, there are no one-shots of monsters for the most part in 4e, but my character did it every fight in PF and it made everyone else's character look bad and wasn't fun after awhile.
My attack bonus was also sommuch higher than everyone else's, so if the DM made it tough for me to hit, it was impossible for the rest of the party. Likewise, the paladin's AC was double the rest of the party, so in order to challenge the paladin, the monsters would hit the rest of us every time.
In conclusion, run whatever you and your players are more familiar with. However, the combats in Pathfinder are much more difficult to balance against the party. 4e never has the problem of making a fight trivial for one character and life-threatening for another.