Needed more RAM.
Went brilliantly on the MBP. However went though some (putting it mildly) getting Windows 7 on Boot Camp to work. Booted into black screen and neither Apple, Microsoft, nor any Windows tech forum was any help. After half a day found it was the AMD Catalyst and ATI drivers that needed to be uninstalled and reinstalled. All working well now!
See above regarding Boot Camp. (Almost all the Windows forum posts are about incompatible or broken RAM. Not one single thread about RAM that works and is compatible with good solutions. Lots of going into BIOS and work things out there, a bit of a problem as macs have EFI...