punkfolkrocker - I'm a linuxer, paying for software isn't a thing that comes naturally to me. But a) I've been doing some stuff with a friend who uses Tracktion, so it made sense to be compatible with him, and b) I find the interface just so much simpler and more straightforward than the free equivalent (Ardour - I find it fiendishly cluttered). I've seen reviews that give the impression it's "unusual", but as someone who'd never used a DAW before that doesn't bother me. Also, (hint hint ?) a couple of weeks after I'd downloaded the freebie, they mailed me a Special Reduced Price Offer on the current version. (In fact, that's the only, very minimal, downside I'm aware of, they seem very active in mailing me with opportunities to buy more stuff ... not a problem, really).
I may well continue to use Audacity for simple things, I don't really see them as competing.