I know there are basic differences like no plugins and such. But if I use Visual Studio Pro at work and want to do some ASP.NET MVC apps at home, would I find Visual Studio Express a hindrance?
Visual Studio Expression is a free but less featureful version of Visual Studio Pro. As you've noticed it doesn't support plugins and a number of other features. It does support the editing of MVC web applications so it should be just fine for your purposes.
Here is a very useful FAQ page for Visual Studio Express