My trial is up soon, but I've been using 365 Home Premium Preview. Just like Win 8, it takes a little getting used to. I have it set to sign me into my MS account as soon as I open any Office program and it allows saving to HDD or to your Skydrive. The only real drawback that I've experienced were minor slowdowns while using it on my older laptop (Celeron single core 743 1.3GHz, 2GB 1333 RAM and 5400 RPM HDD, Draft-N wireless). When using it on my desktop, it was much more responsive.

We are using a mix of Office 10 and Office 07 Professionals at work, and files created on 365 worked just fine on the older versions. I did not have any problems with 365 changing my default printer and have been able to print just fine. The only program I haven't used with the preview is Access, but everything else works just fine.

Honestly, just like the Win 8 preview, I am sad to see it end If MS changes their license back to allow 3 PC's again for the 2013 version, I will probably get that for the $100-$150 price, but if not I will look deeper into the yearly $100 365 subscription. When this preview expires, I will go back to using 2007 Professional that I was able to get while a student, but as soon as it's affordable I will be upgrading to 2013.