It's a slippery slope argument at best, sorry. In Parallels 3.0, the whole argument about clicking on an attachment or URL in Outlook and having it open in a Windows program is nullified since the SmartSelect feature lets you set Mac-native programs as file type and protocol handlers in Windows.
I gave up on personal finance software on the Mac. I'm now using Yodlee Moneycenter. It's not as fully featured as, say, Quicken, but it works well enough for me and being a webapp, it's available anywhere I can get access to a computer and a browser.
Parallels and VMware Are Gateway Drugs to Windows
Mac Personal Finance Software = Disappointment