Need help deciding which Chanel tote!

You definitely can't go wrong with either one. I love my cambon tote and it goes great with casual and with dressy looks. I would definitely grab a cambon before they really discontinue it. medallion tote is always going to be there.
 
If you're going to use it for everyday, I would go with one of the totes made with the caviar leather. It can take a beating and not look like it. I have a PST and I love that it looks as new as the day that I got it.
As for the Cambon, it's still around and will be back in the fall again, so there's no need to rush.