I'd love to have an Exchange setup, but for now I'm using POP3 (with SSL). I have the option of using IMAP, but frankly I don't like having 15 different inboxes. I much prefer to have 15 POP3 accounts all delivered to one inbox, especially since 90% of my email comes to one account. Syncing via ActiveSync works good enough for my needs. I'm rarely away from my computer for more than a few hours or days at most. Receiving emails isn't usually vitally important, and I'm still able to send email from my Pocket PC at those times.
(Alright, just got back from watching the Perseid meteor shower for a bit, and since it's 4:30am here, I'm off to sleep. 
)