Laptop Sleeve Cushion

How to prepare your laptop while traveling?
I am going oversees and my new macbook will be seeing a lot of airports.
Do I need a plastic case, or will traveling with the laptop in a cushioned sleeve (inside anther tote) be enough? Any recommendations for affordable protective cases would be much appreciated.
Thanks in advance!
I traveled with my HP DV7 in my carry on messenger bag, but it was wrapped with one of my sweaters for padding. It arrived safely.
Incase 15″ Protective Sleeve Deluxe review