I'm on AT&T, so I don't have Data Sense

. Can someone who has Data Sense give me some idea of what data usage is with an email account set to sync "as items arrive". Specifically, it would a live.com account. Or if anyone knows in general how much more data is used with that verses using the 15 minute option. Any information along those lines would be helpful! I'd love to set email to update as things arrive, but don't want to run into any data usage surprises halfway through a cycle and AT&T's data usage information by text can be stale as long as 24 hours!
thanks again WP community!