I've declined twice at BWI. Both times I got very "friendly" pat downs and some flack about it being less hassle to go thru. It was also very difficult to see my stuff as it was left just sitting there on the conveyor. On top of that, someone tried to walk off with my laptop but "returned" it to me as an "accident" (funny, it didn't work right after getting it back) after I asked for an LEO.

I'd still refuse. Just expect to get hassled if you refuse, and also ask to have your stuff brought over so nothing walks off.