Standard Edition:
RRP: $99.95
Currently: $22.48
Deluxe Edition
RRP: $119.95
Currently: $29.98
Gold Edition:
RRP: $149.95
Currently: $37.48
Ultimate Edition:
RRP: $179.95
Currently: $44.98
The game is cross play compatible between PC, Xbox and PlayStation
The Deluxe Edition is currently on sale on Xbox (See here: https://www.ozbargain.com.au/node/768006)
Reviews here - reviews well. Lots of fun.
I've never used them but it looks like gamersgate have everything ~10% cheaper. I don't know if there will be any additional credit card/currency conversion fees but the amounts are in AUD. Can also use cashrewards for 3.5% cashback. Should be legit as they are on ITAD. Unfortunately it's not a Steam key and will need to be activated on Uplay.