They actually really beefed up the internal speakers for the 27", if that's what you have.
It just struggles with low-end stuff. I wanted a B&W setup, but at £400+ it's a little pricey.
I went for the Swan M10 setup after some heroic reviews I read on MR. You'll need a step converter to run them as they're not distributed over here but they're epic. The woofer's so punchy it'll actually move my MacBook on the desk above.
IMO, the Bose system (the sub-£500 ones, anyway) sound VERY tinny. I actually prefer the internals to them. lol.
If you're interested, I'll email you the site I ordered from. They were £180 shipped to my door, all taxes etc.