Scott, I would be the first to admit that I know next to nothing about the printing process as a whole and the vendors I'm looking at use metal dye sub process on ChromaLuxe sheets.
The conversations have been referencing ICC Profiles for the soft-proofing process...all claim that they do not exist. That makes no sense at all to this printing ignorant consumer.
Providing an ICC profile that you can only soft proof with is a half baked CMS if I can be that kind!
You need the profile to soft proof and convert the image on your end. You need to see and control the rendering intent and soft proof to look as you desire and that conversion has to be maintained value for value when fed to the output system. To send a profile for soft proofing then just demand sRGB or something other than the color space you just used is waste of time IMHO.
Making the profiles is no big deal. If someone like a lab provides a profile to their customers, they may
have to pay a fee to the company who's software built the profile. It's not that expensive in the grand scheme of things.
Process control is far more important and depending on the process and workflow more difficult. I can't understand why this would be an issue but I don't know anything about this process other than I've measured them. If a lab can keep an E6 lab in line, like the old days, I can't understand why they can't nail a partial or fully digital process. If one can keep a analog or digital press in a tight process control, I can't imagine a reason why this process wouldn't be as tight or tighter.
I don't see why a good lab can't supply good profiles to use as designed and have a path for people who don't care: Just send sRGB. But providing a profile and demanding sRGB is a sure sign to forget this lab's idea of color management.