I'm not sure, but one of the questions preceding that one might be, "CAN I have an extra 100 f/s when my 185 gr. Gold Dots are 1200 f/s?"Is it worth it to me to have an extra 100fps when my Underwood 185grain gold dots are 1200fps?
At 1200 f/s with a 185gr. projectile, it sounds like you may be at the max end of the velocity scale, until pressures rise into the .460 Rowland range.
I'D CHEERFULLY trade 185gr. @ 1200 f/s for 200 gr. @ 1100 f/s or a bit more. Hodgdon reports 1142 f/s with their 8.2/CFE-Pistol/200gr. LSWC, but it's from a test barrel, and "real gun" velocities seem to dip under 1100 f/s. IF, with a .45 Super "upgrade" (sans "fully supported/ramped barrel"), I could get 1100 - 1150 f/s without stretching or battering anything (much), I'd be inclined to try the "upgrade".