Having trialled Waves LA-2A emulation, I found Cakewalk's to be better. Better to the point I use the AU version in Logic as well as the Windows version. I've no real idea how accurately any of them emulate the hardware of course, not having a hardware LA-2A to compare them to, and the original units are now so old surviving examples are probably not as they were when brand new anyway.
I just find Cakewalk's one easier to dial in, more flexible and a bit more 'musical' for want of a better word. You might disagree, and the Waves one is certainly worth trialling to find out. Just don't pay full price unless you really need it now, almost everything Waves makes goes on sale sooner or later.