I've recently upgraded from a 28" Avant to a 7-40 - and the BV8 was never an option for me, the design just isn't special enough. If a TV's going to be around for a few years it needs to needs to look good - the BV8 looks nice, just not special.
Quality of the BV7 - aswell as built in option of Blueray swayed me.
It took me 5 years to get SWMBO to swing for a new 7 though - good luck swapping after 3 !!