I like the circle backs a bit more myself. But there are different reasons for liking each back. Magicians tend to like the circle back more because it's a less busy-looking design (the fan backs look vaguely like the old DeLand automatic decks). A design that's overly busy can make a spectator think it's a "special" deck, even when it isn't. XCMers like the added flash of the fan back, though some would go for circle backs, I imagine.
It boils down to your preference - the quality is 100% the same on both. My personal favorites of the four possible combinations would be blue circle backs. A lot of gaffed decks come in red-only, so I see more red than blue around, and I like the simpler back design over the fans. But my tastes to be 180 degrees away from yours for all you know.
If you're looking for standard red/blue, the cheapest ones I've found so far are through T11. If you find them cheaper, let me know where, please! I'm not in the market yet, though - I recently snagged some freebies (including traditionally cut Bees!) from USPC for doing them a favor.
If you have the extra ducats, consider springing for a black deck or two. They look really cool while still appearing familiar enough to not scream out "LOOK AT ME, I'M A SPECIAL MAGIC DECK!!!" But remember those are limited-edition collectibles - not the kind of deck you wanna drag through the mud.
I really wish USPC would branch out with the Tally-Hos a bit more. USPC considers Tallys a regional brand, sold almost exclusive either online or in the NYC Metro area (there's a few mom-n-pop stores in my area that sell them and Bees, no Bikes). Most national chains won't touch a brand that isn't instantly recognizable anywhere in the country that it's sold. If USPC pushed it more it could be a national brand, and with increased volume in sales perhaps even come down in price.