If you are using a Stageline with a good quality external power supply then it will outperform 323 cards in a 32.5 for a number of reasons. The main reason is that each channel has a separate dedicated power rail rather than sharing a single rail, possibly with other boards, in the 32.5. I'm not sure but it's also possible that more recent Stagelines are more like the 523 than the 323.
An alternative approach, which is well documented in the DIY forum, is to feed the 32.5 with a single raw dc supply and put individual regulators inside the 32.5 - one for every board that you are using. That will improve its performance on all sources and cost a great deal less than a Stageline plus power supply.
malcolm