Hey Babysinister,
They're fully compatible. The only thing you lose over the kit lens is
that 28mm isn't very wide when you include the FOV crop factor (~38mm).
Watch out as well which 28-105 model you get. The f/4-5.6 ones aren't
worth the money - poor image quality and cheap construction. Try to
find a f/3.5-4.5 on ebay instead - they're an older model and not sold
anymore, but have better optics and features.
Jules
http://www.shuttertalk.com - the friendliest digital photography forums
on the net!