When I owned my coffee shop in Manhattan, Jim was kind enough to ship his PowerPlay demo speakers to us so potential customers could audition them. I had more than a few days to spend some time listening to them and I was very impressed. I also had concerns about the long term reliability of the plate amp. This got me thinking again today after reading your post...
Since Jim is the king of bespoke speakers in the industry, I don't see why he couldn't build a speaker that contained a passive crossover, two sets of binding posts and a rotary selector for "External Active" and "Internal Passive" setting. Jim could build small enclosures for the plate amps and the customer could have the best of both worlds. If the owner needs to sell these it would be more attractive to a potential customer.
I might just ask Jim if this option might be feasible for SS 7F (originally a passive crossover design) I just put in.
I would venture to guess that many people may share my perspective on powered speakers.
Something as beautiful as a Salk speaker, or something similar, that is expensive, is a long term investment for enjoyment.
A few years down the road if your powered plate amp breaks you are hosed. You have a 5-15,000 dollar paperweight, especially if the plate amp has been discontinued like they tend to do.
With a passive speaker that is well cared for, broken external electronics can be replaced and the speakers are still great.
With the way things are manufactured these days, will a plate amp go the distance? It’s a roll of the dice. The SS9.5 sounds great and will last a decade or more for the same financial investment.