well if you intend to use a network to render faster, thats pro only
so potentially it can render faster, as long as you put the money into
computers and stuff too :)

if you're using it for small time hobby pics, then standard is the way to go

speed/better/different, is same as far as i know

buying hex2 from daz, you pay for club+hex2=$32
owning hex2 gets you a companion discount on C5 $200, C5P $400
club discount gives 30% off, C5 $140+$32=$172, C5P $280+$32=$312
incase you didnt know :)