I use a VM on my mac to run Windows for the sole purpose of using remote desktop to my work laptop. Yes, I know that Microsoft offers a free RDC client for the Mac. But the client doesn't support multiple monitors on a mac and that's a show stopper for me. I've been using VMWare Fusion 2 & 3 for a bunch of years now and I can't say I was ever really happy with it but it seemed to do the job. But I recently compared VMWare Fusion 4 to Parallels 7 and for my use case Parallels 7 is slightly better than VMWare Fusion 4 and with Parallel's upgrade offer for VMWare Fusion 3 users it's a no brainer in my opinion to switch to Parallels 7. So I have. More details below the fold.
1 Keyboard Settings
I have a Microsoft Natural Ergonomic Keyboard 4000 attached to my mac (I love that keyboard btw) and I want it to work exactly like a Windows keyboard when I'm in Windows. In Parallel's case once I turned off all the Mac shortcuts the keyboard worked flawlessly. In VMWare's case turning off all the shortcuts still left one odd behavior, VMWare switches my windows key and my alt key. To fix this I had to enable key mappings and turn off all the preset key mappings and create new key mapping that mapped the command key to alt and the options key to the windows key. Once I did that everything was fine. So I'd call the keyboard settings a tie.
2 Running remote desktop
Both applications can run remote desktop with LAN experience (e.g. with all the graphics and such) without problem. This is actually new because in VMWare Fusion 3 I constantly had failures if I tried to run remote desktop in full quality mode and had to turn things down. My general impression however is that Parallels runs remote desktop faster than VMWare Fusion 4 does. The difference is not huge but it's just enough for me to notice it. So Parallels 7 wins this one.
3 Full screen mode
I live in full screen mode, that's the whole point of the exercise, right? So switching from full screen back to my mac is something I want to be pretty flawless. Parallels has the design for this nailed. When running full screen the Windows VM looks like another desktop. When I want to switch back to my Mac I can just put the mouse at the bottom of the screen and the doc pops right. When I select a Mac application I am taken to my main desktop and I'm completely back in Mac land. Note however that from time to time Parallels seems to get confused and putting the mouse at the bottom of the screen won't bring up the dock. I sometimes have to try one or two times to make it succeed. But in general it works pretty well.
VMWare Fusion 4 also has a full screen mode but it's really just a big app window, it's not a separate desktop. So when I want to switch I have to minimize the screen. It's really not a big deal but it's just not as slick an experience as Parallels. I've also noticed on many occasions that when I maximize the screen VMWare Fusion 4 will forget about my second monitor. and won't draw it in. But as soon as I click anywhere in the second monitor VMWare Fusion 4 instantly fixes things. This is actually a vast improvement over VMWare Fusion 3 where coming back from minimize was a gamble that often left my screen a hopeless mess that could only be fixed by switching out of full screen mode and back again.
So, again, Parallels 7 wins this one.
Upgrading from VMWare Fusion 3 to Parallels 7 costs $30, although the Parallels 7 retail price is $80. VMWare Fusion 4 appears to cost $50.00, I couldn't find upgrade pricing for existing VMWare Fusion 3 owners.
For my use case Parallels 7 is slightly better than VMWare Fusion 4.
If I didn't own either product I suspect I would buy VMWare Fusion 4. It's street price of $50 is $30 less than Parallels 7's $80 street price and I don't think Parallels 7 is $30 better than VMWare Fusion 4.
But in my opinion it's a no brainer to upgrade from VMWare Fusion 3 to Parallels 7 at $30 so that's what I've done.