I'm a big guy- about 245 lbs @ 5'4", size 46F chest, and I do still feel like they're too prominent some days, but on the whole this setup works well for me:
undershirt, at least 1 size below the size you'd wear for an outer shirt (for me this is a L)
underworks 974 ("Cotton Concealer Muscle Shirt") XL
underworks 997 ("Ultimate Chest Binder Tank") XL
Here's a pic:

It ain't perfect, but I think it's about as close as I can safely get. The 974 only has one layer of the nylon compression material, so I think it's probably less risky than trying to use two of the 997s. I've tried it, but I could feel immediately that it was not a good idea- listen to your body. I can't use a tritop or cut off/folded up binder because it makes my stomach look even more huge than it already is. I did ask underworks to make a long, 997-style trilayer binder, and they said they'd think about it.