Looking for feedback from anyone that uses VMWare Fusion on their MacBook Air. Does it perform well when running Windows 7 in a VM? I was concerned about running out of memory with only 4GB, but then figured that any paging done to the SSD would be much faster vs. a spindle drive. So in reality, a VM may perform better on an Air with 4GB of RAM vs. a MBP with 4GB of RAM and a spindle drive. Just looking for some real world results.