Center Channel question

I own the 6700s with PSW404 sub. I just reqad the following on CNET (replace the center channel with a CSI30) which I would ask the members here to comment on.
Thanks very much.

"Because so much of the dialog and soundtrack plays through the front RM2650 center channel speaker it becomes much more evident as you listen to extraordinarily well produced DVD's. To our ears, this is the only potential negative of this system but, to be fair, most systems in this price range suffer from the same shortcoming. Since we were already chomping at the bit to add a rear center speaker for even more exciting 6.1 surround thrills, a helpful exchange of email with Polk customer service provided some interesting options. To convert your RM6700 setup from 5.1 to 6.1, you could simply add another perfectly matched RM2350 sat or RM2650 center channel speaker for about $120 or $180 respectively. Both feature timbre matched 3/4" silk/polymer dome tweeters and 3-1/4" midranges. However, for significantly wider dynamic range, we decided to add a new, larger Polk CSi30 center for $180. WOW! What a HUGE difference! The larger 1" silk/polymer dome tweeter and dual 5-1/4" Dynamic Balance® drivers provide significantly increased dynamic range and are sufficiently timbre matched to the front sats to make for great transparency and seemless sound migration across the front soundstage. With the original RM2650 front center speaker now delegated to rear center, there is no 5.1 "jump" from left to right rear surround speakers - just smooth, fluid sound movement across the rear soundstage as well."