For under $150 they are pretty decent.
The highs and mids are about as good as you can get with a PC speaker set such as this. However the bass and the sub are less than stellar, but passable. The only competitor that goes for less is the Logitech 540 set which has even worse bass. The Z-5300 series, however, has much better bass than both setups, it uses the same speakers as the much more expensive Z-5500 set but with less features. All in all, the Altec Lansing ASA-995 set has possibly the most natural highs of all three, but the lows are way too inaccurate and boomy for me to truly recommend them over the Z-5300s whose bass is too a little boomy, but PC speakers aren't great to begin with. For less than $150 they are decent, for more they are too expensive, that is my take.
Note that I have tested all of these at a local audio shop.