slight hardware changes ,, the pro has avaible 3 times 2 sampler/locator pads where the changes give you 4 times 2 sampler pads/locatores ,, thease are avaible controls by the controller
other than a three led for changing the fx output desigination ,, everthing else is similiar ,
what are your needs for the controller will give you a better chance of chosing the right one , and how much cheeper ,, because the slight differences can be overcomed with keyboard mapping and altered MIDI mappings,
sound card and configuration is the same ,,
also the pro has a slightly different feel in the Cross fader than the pro2 ,, pro 2 feels lighter ,pro feels tighter ,
feel free to ask any
,and there are some postings that give info as to the differences,
as too the efx ,,software yes and that opionis is not a concences ,,but there are thoughts for re vamping the fx ,,
if your not familiar with Cross try the free version ,,even though limited it will give you a feel for the Cross platform ,
just a oppunity to get long winded 
