/lit/ - Literature

I've got a 700 word bit of exposition on page 14 (A4 pages mind you) of my novel which I'm unsure on keeping in or taking out.
On the one hand my editor thinks it's vital since he feels I haven't stopped at any point during the book to go 'right this technology works like this' to the reader.
But on the other hand it's a first person novel from the eye view of someone that grew up with this technology, they wouldn't stop and give an 'as you know' any more than you or I would when we get into a car, doubly so with it being so early in the novel and my gut tells me that exposition in my sample chapters is going to fuck me out of some literary agents somewhere along the line since some of them froth at the mouth over that sort of thing.
But on the third hand the bit I have written tells you a fair amount about the character and his attitude as well.
It really is a toss up, I'm tempted to send off 50-50 with or without it..
Seriously tempted to just go with my gut and throw it in the fuckit bucket.