Not sure on crop, but its doing a lot of de-fisheyeing at the same time - so not all the crop is down to the stabilisation.
Looks like its using around 85% (you are losing 15%) of the frame (see attachment) - But I presume if the motion is a lot less, the crop won't be so heavy.
As to processing time - I've only got it on my travel Air 11" at the moment - and AfterEffects is AWFUL, FCPX runs Butterly smooth on it, yet AfterEffects can't even preview without dropping frames.
I get a feeling from reading how this works, it won't be a universal plugin (Premier, FCPX, Motion etc...), as its using the builtin AfterEffects motion tracking to perform the stabilisation. So might mean round-tripping to AfterEffects 
But it took around 14mins (roughly) to render that 11second (497 frames) clip on my Air. Minute per second of footage say? Ouch.
Haven't got around to running it on my i7 MacBookPro with more ram and a proper GPU, but if its anything like NeatVideo, unless you have a CUDA enabled card, and a decent one at that, its gonna be slow.
Will have to see/understand where I would run this in my editing flow, I presume on a per clip basis.
