3g connection really discharges the battery quick. i dont have 3g on my n900 but i can tell because i am using a device that has 2g and 3g.

also, my n900 drains 10 percent of power every 30mins using joikuspot (n900 is the client and my n86 is the host). so ad-hoc connection also is a battery killer.

but in any case, my only problem in mfe on n900 is the sorting of e-mails (unread, received and from). but i realy like the sync on the calendar. works superb!