I was looking for a center channel to go with my B&Ws and was going to listen to the B&Ws in the $500-700 range, to go with my B&W towers, but I saw Audio Advisor was selling the Infinity Intermezzo 3.5c for the same price. Can't really find much about the Infinity except the self serving reviews on Audio Advisor.
The Intermezzo can be had for $470 new in the box (ebay) if you don't care about authorized dealers. A 250-watt amp self powered center that retails for >$1000 and has killer crossover capability for under $500! I've heard it. Wow is all I can say. You won't find much talk of Infinity on this forum. What do you listen to the most? DVD-A, Action movies, DTS music, or what? The 3.5c is versatile and can go very loud and clean. It look gorgeous. Its sound is unique.
The $600 B&W center (#?) I heard sounds different but still great. It was more or less accurate with great mids and sounded like B&W. Voices were very nice. Someone very familiar with the B&W line should be able to help more.
If it was me though, I would probably stay with B&W to get as precise voice matching as possible. I have always though that was critical.