They do get viruses, and have for a while, but most have been basically nothing / fixed straight away. They're bound to get more at some point.
I don't really mind. I use my PC a lot without anti-virus protection, and rarely have any problems, I turn it on and check once in a while, but as long as I don't be silly, and make sure I know exactly what I'm downloading/installing, it's fine!
As for the Macbook itself, I've never come across a laptop that has been as well built as my Macbook pro. I know it's expensive, but I need a laptop that is sturdy, that I can carry around with me EVERYWHERE and that runs Logic Pro - as that's my main DAW.
If I have any problems with it, I can go straight into the store and ask them what the problem is (If I don't already know) and get it sorted out straight away. My first Macbook was almost completely replaced within the three years that I had the warranty, so when it ran out of warranty, it was almost like a new machine.
The education discount definitely helps though.