I think Microsoft has just lost the USP of their Surface RT version; yes I know you need a 365 subscription to run Office on iPad, but in my current role working for a large computer/electronic retailer most people only purchase the MS Surface for the simple fact that it has office capability. It will not be long until the iOS versions of the office apps have full functionality (over the iteration of many releases I would imagine). This is a real win-win situation, a huge Apple fan myself I feel Microsoft is making real pace with Office and there additional software, yet they are loosing touch as Windows 8 does not know what it wants to be - a desktop or tablet OS.
TL;DR: Office is great, especially now it's on iOS. Windows 8 and MS Surface are not great.