I have these which I bought several years ago, the Logitech Z-5300e. They're basically the ones you listed, but larger. They do sound quite good, and they've lasted for years without issues. One of the things I really like about them is the control deck. Instead of having the controls on one of the speakers, they have a separate remote-like device plugged into the sub that controls everything. It also has a headphone jack which comes in handy, and it uses the built-in amplifier to power the headphones. I have really nice studio headphones that sound awful when plugged straight into the PC, but sound beautiful plugged into the Logitechs.
Normally I would recommend the best, the Klipsch ProMedia 5.1, but I don't think that's within your price range. The Logitechs should be quite good enough.
