Hey Paul,
Have you considered going 3rd party for your telephoto? You can get a Sigma 500 pretty affordably (at least compared to the big boys).... I have not used one, but I am incredibly impressed with the Sigma 120-300, which cost less than half of a Canon 300 F2.8.
This is the review I wrote on it:
http://www.nwpphotoforum.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=37426James
