Center channel speaker OR 3 identical front speakers ?

I'm considering the Infinity Primus P163's for my front speakers. But the center channel speaker is more than double the price. There's no problem if I use 3 of the P163's for the fronts, and skip the center channel speaker, is there? That is supposedly ideal, isn't it? All 3 speakers will be at the same height, sitting on a shelf. Usage is 70% movies and 30% music. Thanks.

Yes. It needs to be upright, correct?

Does anyone have any recommendations for nice bookshelf speakers comparable, or better than the Infinity P163's? They need to be front ported or sealed. Budget is $250 or less for 3. Thanks.
Edited by Jim McC - 1/20/13 at 2:08pm