The biggest issue you will have is that you just said specs... then gave us dimensions. If you take a look at the Bose website, you won't find specs. Specs talk about power handling, effeciency, frequecy response, things like that.
Bose gives you size and weight.
This is part of their marketing which limits what you know about the system and the ability to compare it to any other product directly.
If all you care about is the size, and not the sound quality, then you have already made a decision. You aren't going to get more sound quality from another company who uses the same size speakers. It is not just a limiting factor, it is a major limiting factor.
Knowing that, if you walk through Best Buy or Circuit City you will find a host of products that LOOK similar to what you are seeing from Bose at a fraction of the price that operate similarly and have similar functions. As long as it is a major manufacturer, you can rest assured that you are getting similar quality for a much better price.
You typically won't find much similar though as most manufacutrers are focussing on sound quality, not marketing, and thus, are forced to used quality components to build a reputation for quality. This is how speakers from companies like Axiom, Energy, BIC, and Definitive Technology, in all sizes are so well regarded. Maybe take a look at the Definitive Technology Mythos Gem speakers.
http://www.definitivetech.com/loudspeakers/mythos/mythos_gem.html
or, try a $500.00 or less package from Yamaha:
http://www.yamaha.com/yec/products/HTIB/HTIB_DTX3100_1.htm
Yamaha actually has all types of HTIB packages at all sorts of prices that, at the very least, are more accurately priced for the quality of the product.
As always - your money - your choice.