You wouldn't be asked first - I hope that's clear upthread - but it shouldn't matter and generally you should get your first preference. TLV and IAD are both status rich lines, anything else will be new crew or some other special circumstance. I am not often asked first, but I've always had my first choice. For IAD it doesn't really matter where you sit, in terms of rapid exit, but it does matter where you stand! TLV - getting off early makes no difference, the slow down is the machines and long walk to the border agents.