No offense, but anyone buying a product based on potential future updates is doing it wrong. While I get your frustration to some degree, I think you're off base here.
At the time of purchase, why would anyone have thought any different though? That's what customers were told. The big hole is where the future upgrade for the power amp goes right? What about the customers who can't afford it at the time, who wanted to upgrade later?
It's nice to have a choice.
As a consequence, my head isn't upgradeable anymore, has lost it's second-hand value and the only customer path is a convoluted rebate.
Again, I'm sticking with it and love what it does. I just think (rather obviously) this could have been handled a lot, lot better.