My Home Theatre designer has "upgraded" my Zone 2 in-ceiling speakers from Phase Technology CI 6.2's to Klipsh CS-650-RSM. Is this really an upgrade? The Phase Tehcnology speakers have a better rated lower frequency, assumably due to the fact the tweeters are not mounted in the center of the driver but rather on the edge of the enclosure. Also, the tweeters on the Phase Techs are .75" vs. .50" on the Klipsch. Any help and opinions would be appreciated before I start mounting speakers to the drywall.