Don't go 2.1. Just go decent 2.0 or 2.2.
The things I read for the Logitech is that they have a huge gap in the middle-section of the audio spectrum. Exact the section where voice and most instruments are situated. They simulate much oomph in the lower end, and they have bright tweets, but nothing in between. I use normal midrange-tweeter combo's with a 2x80 watt amp, and that leaves the Logitech biting dust. Even the bass is better.