I think you'd be happy with either choice. If you've had the 60's for less than 30 days I think you can upgrade without paying anything beyond the difference in $$ between the 60's and 80's. If you're over the 30 days you'll need to speak with a representative from Axiom about that(either way actually).
Whether you want to go the 80's route is up to you, both speakers will make you happy, I'm sure. However if you're a "What if" kind of guy(most of us are), you've got the room for the 80's, and the wife has left you this one time chance as an upgrade....
