I would try phantom mode first and see if you like it. Phantom mode worked well for me, but only when I was sitting dead center. As soon as I sat off to one side, the dialog ended up localizing to the main speaker I was sitting nearer. I ended up getting a center channel because I want to be able to sit anywhere on the couch when I watch movies, and because I want guests to have a great experience as well. If you end up trying a center channel, make sure you use a *matched* center speaker as well as identical amplification and cabling on that channel. In my setup, watching movies with a center channel sounds so much better, I wouldn't go back to phantom mode. In fact, I now exclusively listen to stereo music in Meridian Trifield mode, but that's fodder for another thread!
Tomer
Tomer