17 inch desktop replacement laptops are great until you have to move them. They have the tendency to flex under their own weight and require extra protection and briefcases large enough to accommodate them are unwieldy. The best strategy is to get a well built sleeve that holds only the laptop. For this, I recommend the Tom Bihn Brain cell. If you still need room for other accessories, there are other options but the Tom Bign is still my top choice.
It’s really simple but it’s solid, does it’s job and (most importantly) its easy to get your computer in and out with one hand. Use the “Fit List” to pick a size. ($60)