8.03 versus 8.04

Can anyone specify from his/her experience what would be the benefits of using postgresql 8.04 versus 8.03  in terms of
reliability and/or performance.  
My organizations intends to upgrade one of the servers from 7.3 to 8.03 (the version of the secondary server) or to
8.04which is the latest 8.0x.  I would tend  to chose 8.03 which seems pretty stable so far but I would like to hear
fromother from other people.   
We are talking about a database which has about 100GB data. with some of the tables holding 20GB or more.

thanks,
Alex Cotarlan