I've just updated my PC to an iMac (please no discussions about the advantages/disadvantages of either!). My wife would like to have Microsoft office as that is what she is used to for her documents and spreadsheets. I've seen ads for full price from Microsoft (£120ish), key downloads for Microsoft for £65 (current offer today) and key downloads from other vendors for about £22. All these are on Amazon. Is there any reason not to go for the cheapest? I presume the software is downloaded from Microsoft and the purchased key (from wherever) is entered when it is run.