Years ago I put about 100 or so through my 625-4, and no ill effects were suffered. I have since decided that it is not worth the chance and stick to standard .45ACP loads.
My 625 has a 3" barrel. I experienced no extraction problem. Recoil, noise and muzzle blast were increased over standard .45 ACP. It has been a number of years but IIRC, I would say to levels close to shooting medium to full power .357 out of a 4" N frame.