As far as functionality goes, the steelseries macro software (and you have to use macros for standard key presses outside of WoW) is shit. I mean fucking terrible. If you assign say, the "1" key to one of its buttons and you're click happy, it behaves like a keyboard and puts the input into a buffer with delays. To wit: it will keep spamming 1 for you long after you stopped pressing the button. Even if you press another button. This is terrible behavior for mouse software -- but it is a software issue so it can be fixed. You can remove the delay from single keypresses, but you can't remove (or edit!) the delay on a multi-key macro -- except to send everything simultaneously. So if that'd work for you... I guess you can ignore the preceding.

The naga's mouse4 and mouse5 buttons are also horribly placed.

The naga's buttons feel better than the cata, too. The cata's buttons feel mushy to me.

If I had to choose between a naga and the cata mouse, I'd take the naga. If someone asked me which were better for most people, I'd say the naga. If the cata mouse had the naga software, I'd be more neutral, but it doesn't and I don't play WoW anymore.