I generally agree with what lowtech said here.
I would only add my personal annotation, and that is that various people, including the staff at the physical shops, love to play with SAKs when they are exposed somewhere. I have seen quite a few times new SAKs (in stores) that were full of fingerprints, small chunks of dirt and dust and small scratches (mostly on the cellidor scales).
The last SAK I bought for myself already had some small scratches on the scales (I didn't notice them in the shop) and the combo tool, it also had surprisingly dull blade. That's why I now request the one that's been packed in a box, sitting somewhere in their drawers, then I examine it. Especially when I buy one as a gift for someone.