I don't have a working suit solution yet so I would love to hear what you have that works for you and learn from your lessons.
My wife carries primarily shoulder -- we found a quality one which works really well for her, but it wasn't cheap. I don't remember her DTFS. She carries vertical.
We both see advantages of horizontal carry, but it... feels awkward. To both of us. Plus you are then by definition painting everyone behind you at all times. : : shudder : : Vertical carry, thank you very much.
(The one time painting the guy behind you would be great is to ward off a rear naked choke hold, but we'd have to practice the ever loving daylights out of that -- talk about dangerous shots! [I can hear John cringing at me in the background LOL])
I have a cheaper shoulder rig I'd meant to use when wearing a suit or driving in the RV, but it doesn't work well, so it basically lives rolled up in a ranger band in my transport Vault just in case somehow that's the solution I need someday.
Planning to get one from the same manufacturer she uses, but it hasn't been a high priority so we haven't dished out the bucks yet. I've gotten the Enigma dialed in so well I often forget I have the thing on, and that includes whilst driving. But 6-10 hours of nonstop leisure driving might still warrant a shoulder rig. I ain't gettin' any younger and my circulation ain't gettin' any better LOL.
Anyway, looking forward to learning about your suit solution (and the evolution of it). Tux I got; the cummerbund covers the grip nicely. But regular suit? I don't have an "untucked shirt" option, and I'm an absolute geek about concealment.
Very much looking forward to hearing what you've come up with. I'm floundering a bit.