"In 1989, Seattle businessman Bernard "Bud" Greer purchased the Sohmer company, which also held the George Steck, Knabe, and Mason & Hamlin names, technical specifications, and manufacturing equipment. He moved these to a piano factory in Haverhill, Massachusetts, which he had recently purchased from piano manufacturer Santi Falconeâ€”from whom he also purchased the Falcone manufacturing specifications and naming rights. He named the new enterprise the Mason & Hamlin Companies. Greer's goal was to resurrect the Mason & Hamlin pianos of the pre-Depression era by returning to the original specificationsâ€”including Gertz's scale designsâ€”and use of materials. A few changes were made, including the use of Renner action parts and slightly longer keys. From 1990 to 1994, approximately 600 pianos were manufactured, mostly Model A and BB grands, along with a few Model 50 uprights. Greer sold the company in 1995 to Premier Pianos, which continued production at a reduced pace until selling the company in 1996."
From the Mason and Hamlin Website (which doesn't mention Greer's contributions and innovations) :
The Burgett brothers purchased Mason and Hamlin in 1996.
"Their first step was to use sophisticated computer software programs to archive original Mason & Hamlin company scale designs, jigs, fixtures and templates. Preserving these important company assets was paramount. Then they invested millions of dollars in high-tech computer controlled machinery and equipment to increase efficiency and productivity in the factory. Next they found experienced craftsmen and began making the new Mason & Hamlin pianos.
Wisely, the Burgetts retained many important original features and designs (including Richard Gertzâ€™s Tension Resonator), and by incorporating technological advances made in piano manufacturing during the last few decades, they not only recreated the Golden Age Mason & Hamlin pianos, but in many ways improved on them."
I offer both of the above narratives in response to your statement that "in the early 90s they got back to making them to the standards of the pre-Aeolian pianos." It has been my understanding that the process of going back to the original designs took place over several years. I've always been under the impression that this process was more fully realized in the pianos built by the Burgett brothers. That said, the pianos built in the early 90s had to be somewhat better than those from the Aeolian period.
As for size and power. If your current 6'5" Yamaha G5 isn't blowing the roof off your house, I doubt that the 6'11" M&H BB will blow it off either. The G5 is often described as a big piano with a big sound, suitable for small concert halls. The same could be said of the M&H.
My own 2003 M&H BB can be quite powerful and loud - but I rarely raise the lid when playing it - so the tile roof of my house remains intact - and my wife hasn't given me an ultimatum (choose her or the piano).
As for the specific piano you are considering, my advice would be to have it checked out by a technician to determine what issues, if any, need to be addressed. With an instrument that is 25 years old, so much depends on how heavily it was played and how well it was maintained.