Okay...
Once I get approval from a family member, I'll suck it up (pun intended) and buy the Prolux. Then I'll buy bags on Amazon. And if I hate the machine, I'll just resell it, preferably locally as I don't want to deal with shipping a vacuum cleaner. It's just too expensive to do so.
The fact that my family is so devoted to bagless shows how effective Fantom marketing has been back in the day.
Oh, and I didn't even get to use the vacuum as a very young child. Only my parents did. Apparently, the Eureka Ultra ESP was a decent machine, but I don't think it was made to clean a fireplace.