@Highland Lofts pretty much said what I would. Find the velocity range you would like to use depending on components you're looking at and powder on hand and buy that brass, watch the carbon rings in the chamber with the shorter cartridges. If price is a factor the 32 Long and 32 H&R brass prices are almost identical when you're looking at the same brand, 327 will be a little higher priced. However, 100 pieces of Starline will last you a long time loading at these lower levels, should be able to load all of them at least 5 times if you don't lose them! I wouldn't bother with once fired brass (you find 32 some but its not everywhere).
If it were me, I would use 327 brass with faster powders at near minimum levels, just for the fact that this brass fills the chamber. But if you go with a
plain lead low brinell Hollow Base you may not have stellar results in 327 Mag pressures/Velocity, the plating on the bullet i'm about to mention below helps hold it together so you can push them a little faster than plain lead... The 32 Long brass would be my last choice unless you are just wanting really light loads. H&R may actually be the most versatile because right under 900 fps would still be a pretty mild load and the top end overlaps the 327 FM's minimum data. Back to velocity, Hodgdon data shows loads across the 32 Long, H&R and Magnum range using the exact same component and powder combinations for one version of wadcutter. Its the "83 grain BERB HBWC" which is a Berry's brand plated bullet. Common powders used throughout these three cartridges with this bullet choice are HP38, Titegroup and Universal. I picked HP-38 powder for this example below:
*WARNING* As always don't use this data provided here, there could always be typos etc. Always check the manual for yourself for the bullet and powder combination you are using.
Starting with the 32 Long the charge range is 2.1 to 2.4 grains for velocities between 680-800
Next the 32 H&R Magnum charge range is 2.9-3.8 grains for velocities between 870-1120
And last 327 Federal Mag charge range is 3.6-4.6 grains for velocities between 1000-1200
All of these loads again are for the 83 grain Berrys Hollow base. Good luck with whatever you choose and post results when you try them out!