I've migrated my PC over to a MBA and am so far finding this a great solution. A few observations and issues to share.
I had to do 3 installs of the OS, first one was due to Msft having me download 32 Win7 ISO so I had to delete that and redownload the 64 bit version. I installed that one and did a few hours of updates. However when I migrated my PC over it copies the OS also and so it created another guest OS instead of adding only the programs and files to the prior install. This was something i was trying to get info on beforehand and just was not able to. So for the record a PC migration will bring over the OS.
This caused some minor validation issues that I called MS to fix which they did pretty quickly. So now I am running Win7 and seeing all my programs and files as before. Printers and peripherals all seem to be connected and running as expected. This has gone amazingly easy considering the technical complexity of this whole conversion. BTW I did a wireless migration and 78Gb took about 10 hrs-12 hrs. Since the MBA has no ethernet port and I didn't want to buy an adapter this was the way I went. d
I have a second monitor that I am waiting for the adapter to come from Monoprice to see that it will work as hoped. I am running ML right now and am going to wait until a release or two before upgrading to Mavericks.
Plugged in a USB hub which had a Neat scanner, Dymo stamp machine and scale attached and VM asked which OS I should associate these with. Cool, windows for now but may move over to Mac later.
So there are a few minor things that I'd like to throw over the fence and see what comes back;
1. In my Computer window it shows a A: floppy drive and a D: DVD drive. Last i checked MBA's don't come with either. Why do these show up and can i get rid of them?
2. I did move to trash the two earlier installs that no longer were needed but if i right click aka two finger tap the VM dock icon, the window shows all three installs with nothing happening when the two phantom ones are clicked. Why do these still show up and can they be removed?
3. In Unity view all I get is a window showing my virtual library, clicky clicky but nothing happens. I think it should be doing more than that. i was under the imoression that it would create a window that i could interact with other mac programs, e.g. drag and drop.
Overall, a happy camper and feel the cost of updates is a necessary cost of running windows on a mac. Can't imagine a company surviving issuing endless free updates for a $50 charge collected years ago.