Another BB emp. here, I would stick with matching the fronts/center but check the athena accomodations, price wise there pair of F2.2s are less then just 1, yea 1 F3 and the Audition series had a ton of great reviews and alot of people talking about how good it was for its full retail price.
If I remember correctly the PAIR F2.2s will run you ~$180 plus ~$54 shipping(flat rate even to Hawaii) about $170 savings, but stick with matching fronts unless you also want to get the Athena center for like $54 more(still saves some cash vs 2 F3s).
Also check as stated before, check the Klipsch accomodations and check some item vs. emp. discount, somethings where cheaper in emp.disc. while others where cheaper in accomodations, they already ad the shipping costs into the prices listed there.
Personally I do not think you could go wrong either way, but get the F3s if you want to keep your center, if you want to save a hundred and some go with the athena C1.2 and F2.2.