Put it this way, if you have a source of cheap lead, say $.50 a lb, you can load a box of .38 wadcutters for about 3 bucks last time I calculated. I think I remember that right and it was a few years ago, but things haven't gone up that much. Free lead, better deal. I load .45ACP, .45 Colt, .357., .380., 9mm, 7mm TCU, and a slew of rifle calibers. I cast for all handguns but the TCU. I've taken to just buying 9mm 'cause it's so danged cheap it ain't worth reloading. But, you definitely save money casting and loading for .45s, .38s, and .357s!
My friggin' Dillon progressive only has 9mm dies for it. I need to get another caliber for it. I'm tossing around whether to get .45 ACP or .38/.357. I have one basic .45ACP load involving a cast 200 grain SWC and a half dozen .38/.357s with various cast and jacketed bullets that I load that would require set up for each, so I'm thinking .45 ACP will be my next die set for the Dillon.
I can say if you shoot a LOT, yes, the casting is the slowest part of the deal. I was shooting IDPA pretty heavy for a few years and was using cheap Winchester 115 gr JHPs I got from Midway or a local gun shop rather than casting for it. The JHPs were accurate and I was simply shooting too much to keep up with the loads. Having to buy those bullets, cheap as they are, it still cost me about 5 bucks a box. Heck, $5.90 gets me a box of 115 Win USA or Remington UMC ball at Walmart. Why bother? I ain't even gonna reload CAST bullets considering the price of the factory stuff.
I have started carrying a +P+ 9mm load I handload with a Hornady XTP bullet that works quite well in my little compact 9. Other than that, 9 don't get reloaded anymore.