Adorama offers the Polk Audio TSx 150C Center-Channel Speaker, bundled with two Polk Audio TSx 330T 2-Way Floorstanding Tower Speakers, and two Polk Audio TSx 110B 2-Way Bookshelf Speakers for $329.99 with free shipping. That's tied with our mention from two weeks ago as the best deal we've seen for this bundle. (It's also $178 under the lowest total price we could find for these items purchased separately elsewhere.)
The center-channel speaker features a frequency response of 53Hz to 25kHz, 1" tweeter, and 5.25" woofer. The tower speakers each feature a frequency response of 33Hz to 25kHz, 6.5" woofer, and 1" tweeter. Finally, the bookshelf speakers each have 5.25" drivers.