I'm no loop guru or master loop slicer, so take my review with some salt, but I have to say I found Cyclone to be a powerful tool. I won't describe its abilities, since others have done so adequately. What I will say is that when I load up a nice ACIDized perc loop and transform it into a drum kit, that I more often than not end up with some of the most musical percussion I've ever heard. The fact that it is MIDI controllable allows me to play that kit from my PX7 pads, which transforms Cyclone into a *brilliant* tool for my purposes.
Would I have bought Cyclone if it didn't come with SONAR free? Honestly, I don't know. I do know that if Cakewalk stopped bundling it, I'd be quite upset.
A few downsides - the UI took a LOT of getting used to for a novice looper like myself. I still get confused by certain things. Cakewalk could have done a better job, IMHO, at making this thing more intuitive. But, for the price, I guess I can't complain.
In summary - an essential tool for loopers, and a great tool for everyone else.