Definitely, get a self-healing mat. Your blades will last much longer, as will the mat.
I love love love my Martelli cutting mat. I bought it online, and they mailed it in a huge flat cardboard box. One of the reasons I bought it is that you can leave it in a hot car, and it doesn't warp (I haven't tested this, but it's one of their claims). It can also be rolled for storage (although I store mine flat). It has a purple side and a yellow side, so if it's hard to see your fabric you can flip it over and work on the other side with good visibility.
You can see more about the Martelli mats here:
https://www.youtube.com/watch?v=Zo3F8NQlN74