Having used both for a couple of years each (not at the same time) I'd have to say that TFS is the more frustrating of the two. So long as you're on a fast corp

Having used both for a couple of years each (not at the same time) I'd have to say that TFS is the more frustrating of the two. So long as you're on a fast corporate network and in Visual Studio it's ok. The moment you try to edit a file outside VS you get problems. Say you're comparing two files in a comparison tool, the files will be readonly. You can overwrite but TFS doesn't know that you've changed that file so you have to manually check it out. Sometimes devs forget to do this. Another bug bear is the Pending Changes list in VS is cached so if you have two instances of VS open things can get out of date and confusing. And try opening your solution when you're off the network. Dialogs start opening everywhere. Assuming you click the right things you'll be ok... until you go back to the office. Then you'll have to prompt it to go back online and wait while it figures out what you changed. I've tried explaining to people who've only ever used VSS and TFS that things don't have to be this way. But they tend to imply that source control is just complex and it's not the tool's fault. By contrast, within a week of using SVN the tool faded into the background and I rarely thought about it.