Some players prefer the more open sound of an isolation-mount. And I also agree that the Big R drums have more resonance and sustain if an isolation mount is used. That's a cool thing about the Pearl ISS mount. As blue-rippler mentioned, these mounts are adaptable to any standard triple-flange rim without actually altering the shell in any way. I think it's a cool idea and I didn't realize that the Pearl arm would fit into a Rogers Memriloc mount. I was under the impression the Pearl tubes were smaller in diameter.
Now that I have agreed about all that, I have to tell the truth and say that I use the regular Memriloc arms on my Big R micro-mini gigging kit (a 14" tom tom in a cradle -mount facing up- for a bass drum and then a 12" tom mounted to it via the Memriloc single tom arm). I know the resonance is reduced but it doesn't bother me. I use drumheads that are sometimes 40 years old. I have several drums wit Remo pre-pie logos. I only occasionally change heads, so I guess it would be ridiculous for me to worry about sustain that much! ;) But, yeah, I would imagine that the ISS mounting system would be a great way to expand the possibilities with those Rogers shells. It would probably sound like a whole different set!
P.S... I have also noticed that the Memriloc mounts tend to stiffen the feel of the drums. The Memriloc design doesn't allow for any "give" when the toms are hit...compared to the way a Ludwig L-arm mount tends to allow the drums to bounce. I would imagine that the Pearl ISS mount would also allow for some bounce and, thus, give those XP-8 drums an entirely different feel, as well.
Good, bad or indifferent, it wouldn't hurt anything to use an ISS mount if it fits into the Memriloc bass drum mount. But, as we all (or most) can agree, permanent conversions are always a no-no with nice vintage drums. There's no need to improve history! ;)
in ANY case, those drums are beauties and what a steal for $400.00!!! WOW!
psssst!...I'll give you $500.00 for them right now! :)