Not everyone is happy to pay thousands for headphones...
I've heard great about both, and Creative do have high end speakers - Gigaworks, being the counterpart to Logitech's Z series. They also have the I-Trigues which seem very nice.
I have the Z-2300 which is awesome, but I'm no audiophile so I can't comment extensively on the sound quality. I previously had a very low end set of Creative speakers, so obviously I can't compare them to my new Logitechs...
If you're looking to go sub R500 I'd go for a Creative Inspire 2.1 set, or if you can get a good price, a Creative I-Trigue 2.1 set. Both of there imo will be better than Logitech X-xxx speakers.
My 2c.