Windows Vista is slow enough by itself! Parallels 4.0 is bloatware like Vista! I hate to come in here and be negative about a company that is trying hard to please...however, I have to say performance wise 4.0 is a step backward from 3.0. I have been using Parallels for about 2 years, version 2, 3, and now 4.0. The install, of this software, requires and advanced computer user. I do like Parallels.... don't think I have nothing positive to say.... The new look is nice; The concept is excellent! I imagine, it is quite a task to try and integrate all these OS's and make it all work well. I sure couldn't do it! Parallels desperately needs a "Virtual Disk manager." A manager that would allow flexibility for speeding up the Virtual Drive, Resizing it to larger and smaller sizes, merging partitions, imaging, backups restores, etc.. I have been having a difficult time getting rid of an unallocated space and resizing my VM to a smaller size. The drive has gone from 30GB to 106GB and now I have to borrow a External drive from a friend to find enough room to run the "Image Tool!" CRAZY! I would like to ask for more "Native like performance" from the Parallels programmers.... Stop add features now.... Follow Apple's lead with the development of SNOW LEOPARD and reduce the overhead required to run this program. Too much code tied to Vista is making my MacBook Pro seem like an old 80286 running Win95..... Slow! Thanks for listening... Customer feedback is how you'll make the the best VM product out there! Thanks for the effort. Mark A. Gardner ATP - B-737, CE500, CE560XL, B.Sc., CFII, MEI. Las Vegas, Nevada. USA