As far as acoustics are concerned, what you have is small enough there is pretty good room gain, like what you get in a car. On the down side, the furthest you can place speakers apart is twelve feet, unless you place them in diagonal corners, which I don't like to do. At twelve feet, you have 1/2 wave cancellation between speakers at 50Hz. If you place them a little closer together, say 10 feet, then the 1/2 wave notch is at 56Hz. You have 1/4 wave self-cancellation from an opposing wall back to the speaker at 25Hz, but that's pretty much out of bounds. These are issues you'll have whether the speakers are cornerhorns or not.

Here are some good articles about room placement that you might find useful:

• Loudspeakers and Rooms for Multichannel Audio Reproduction, Part 1, Floyd Toole
  
• Loudspeakers and Rooms for Multichannel Audio Reproduction, Part 2, Floyd Toole
  
• Loudspeakers and Rooms for Multichannel Audio Reproduction, Part 3, Floyd Toole
  
• Sound System Design Reference Manual, George Augspurger

If you have the room, go with the Audiophile or Professional Series seven π speakers. For a little less money, you might look at the Stage Series seven π or the Theater Series six π speakers. The eight π might be a good choice for you too, because it can be placed in corners or against walls. And if each of these are too large, you might look at tower two π speakers instead.