Parallels Desktop 4 - Disappointment

A couple of months ago, following the advice of an experienced IT professional, I tested VMware Fusion 2.0. Results: far superior to Parallels Desktop 3.0. I decided to pay for a a license, and I have not been disappointed, VMware Fusion 2.0 mounts both Windows XP Pro SP3 and Ubuntu (now upgraded to 8.10) perfectly, much faster and much more stable. When Parallels Desktop 4 was released, I took my chances, paid for the upgrade, and installed. Total disappointment.
There is no way to get Linux Ubuntu to show in *real* full screen. After I overcame the network problems, I could update (still Hardy Heron), tried everything to get Linux to show in full screen. Nothing. I hope, for the sake of Parallels, that they will do something about Desktop 4. Till then, I'll stay with VMware, while watching Parallels' Forums.
Last but not least: from the very moment I started using Parallels, I decided to have patience, to give time to the developpers to do their job. I'll still have patience, but there's a limit to everything.