the 45 super ( or souper if you prefer) offers only a MARGINAL upgrade in performance- it's made from SHORTENED 451 DETONICS BRASS- which was originally made from 308/06 brass, depending on what you had on hand- so from what i understand the family goes like this- 460 rowland, which is longer and thicker - then 451 detonics, which is SLIGHTLY LONGER, and uses thicker RIFLE brass,then 45 super, which is the same length as the acp and uses THICKER rifle brass, and the the 45 acp- so what's the difference?- well, if you use 45super in a STANDARD 45acp, chances are the head will come apart just ahead of the extractor groove, because it's NOT SUPPORTED - if you use 45acp in a 45 super, it probably won't cycle properly- if you go to a 45 with a supported barrel, you might be able to step on it a little- maybe into 45 super territory, provided you use shortened rifle brass or 45 super brass- the other 2 are head and shoulders above in terms of performance , powder consumption,recoil, and everything else- like what a 338 win mag is to an 06- the rowland REQUIRES a compensator to make it work- i don't know where gunnars conversion falls