It sure makes a LOT of sense to experiment, as you're planning on doing.
I just went the opposite way - started with HS6 and 115's, then went to WAC with 124's ...
I saw a slight difference - the HS6 is flatter than the WAC.
BUT, that's the LEAST of my problems - shooting The Very Flattest Load would
NOT get me from a low B to even a high B
So, I bought a TON of WAC and a TON of 124 bullets, and I still have them.
Maybe after they're all gone, I might buy a pound of 3N38 and give it a try - but not
until I use up a TON of WAC.
From my reading here, the 3N38 and the 115 grain bullets is The Best Load. But,
I prefer the convenience of NOT having powder sloshing all over my SDB and
bullets not separating from the case when being jammed into the chamber