I have sony vaio currently...
I personally heard gateway is cheap but not a reliable machine.
I have used, HP, Apple Powerbook, Sony vaio, compaq and IBM, and out of all these machine I think IBM is the best, they don't sell laptops much, but you can find it at an online auction or somewhere.
As for Vaio it's good for graphics, as is Powerbook, but they are too big and bulky sometimes. I am saying that cuz I have had 17" ones.
HP and compaq are not reliable cuz of their screen or their dvd/cd drives are messed up... so it's up to you...best of luck sis