I agree, i recently got a 257 and I was afraid it was going to be too big. It turns out it is the perfect briefcase size for me- I have a heavy 15 inch dell laptop with an extended battery for work, and i carry around its charger, an ipad, a GMAT book, maybe a magazine and the requisite pens, earbuds and other small accessories. It fits perfectly. If the bag was any smaller, i would imagine it would be pretty difficult putting everything in quickly without playing tetris.
Exactly the information I was looking for. I'll probably grab one towards the end of summer.