I have long since committed most of my dollars to RCE presses and dies, although I own many different kinds that I have picked up though the years if I find a good deal. I just purchased a WH conversion kit from the new Corbins, which enables using Dave Corbins "S" dies and "M" dies on a RCE press (Walnut Hill or Sea Girt). The conversion kit is well thought out and well made. The guys I spoke with at new Corbins are working remotely, 4 days per week, pretty laid back, in no big hurry, but friendly and eventually got things done. Anyway, I had never bought any S dies or M dies because I did not have a press for them. Now I can use them on my RCE presses, and I was able to catch a good deal on Flea Bay on some dies. I was also able to pick up a really sweet ejection tool to use with old Dave Corbin "R" dies (no longer made). It also works on other dies designed for reloading presses like BT Sniper, CH4D, and old Herters dies. I thought I would post a pic for comparison of a few of the different dies from different makers.
Left to right
1. RCE WH die (.308) and top and bottom punches,
2. Corbin "S" die (.284/7mm) and top and bottom punches,
3. Corbin "M" die (.357) and top and bottom punches,
4. BT Sniper die (for reloading press) (.500) top punch is captured inside die and bottom punch is shown.
(click the picture to enlarge the photo)
As you can see, WH die size makes Corbin M die look like a toy, even the Corbin S die looks undersized, especially where it threads to the press. The reloading press die has the same thread diameter as the WH, but the main body is significantly thinner. WH dies are simply superior in size and strength to anything else until you get to 1.5" dies designed for hydraulic presses made by RCE, and maybe Corbins in the future.
If anyone else has pictures comparing different kinds of dies, different makers, please post them. I do not have any Blackmon dies or any "H" Corbins dies or any RCE 1.5" hydraulic dies.