I've watched Brentford a lot this season (brought up in Southampton but living locally) - don't want to tempt fate but I think it will be a reasonably straightforward game for Saints : Bees are a good L1 side (and much improved since the change in manager) and will be competitive - don't judge them by the JPT final which was dire- but have had a pretty dismal scoring record this season and a makeshift defence. The man to watch is Jeffrey Schlupp (really) who is on loan from Leicester - a raw young player but lightning quick and dangerous.
I really don't understand the heat between the clubs (or at least the message boards) - one of the things that struck me when I started watching Brentford regularly (for a while we had season tickets at both clubs) was how much they were like Saints in the Dell days : tatty ground but a spirited vibrant club with attitude. And , of course, both have suffered at the hands of megalomaniacs and are coming out the other side - although Brentford do have pretty good financial backing they probably don't have the supporter base to compete with the likes of Fulham and QPR so it's always going to be a struggle.
I don't think the postings on the message boards reflect the views of most people who go to GP and the stewards are generally pretty sensible so I hope the afternoon passes off well. And if anyone is looking for a place to celebrate The Griffin is easily the best pub in the immediate area (although a lot of Bees supporters will be there) or , if you are looking further afield for something more neutral, the Bell & Crown on the river near Kew Bridge is a great spot which always welcomes football fans.
An afternoon of slightly mixed feelings for me but it would be great to see Saints get promoted after a competitive game.