The Sig 226 is a great suppressor host. I don't know if it is the absolute quietest, but it is definitely one of the best.
The TiRant 9 and Osprey 9 are pretty much neck and neck, and are both at the top of their class right now. Personally I fall on the side of the TiRant because I prefer the cylindrical/symmetrical look as opposed to the asymmetrical design of the Osprey, but that's pretty much the only thing I base my opinion off of. They both meter within a few decibels of each other. I know people who are happy with both and I would be more than happy with either if I could just afford one
One thing to think about with threaded barrels is your thread pitch. The "standard" 9mm threading seems to be 1/2 x 28, but Sig factory barrels only come in 13.5 x 1 LH. They used to make a 1/2 x 28, but don't currently. This isn't too big of a deal if you only plan on suppressing this Sig, but if you ever want to suppress another pistol, you'll have to make sure you find the right threaded barrel, which may be more difficult if your suppressor is threaded in 13.5 x 1 LH. (You can also get different boosters from the suppressor manufacturer to work with different thread types which may be an easier option.)
I'm waiting on a suppressor right now that doesn't use a booster, so I'm stuck finding barrels for my guns in only one thread pitch (no ability to swap out a part to accept another threading), so I just thought I'd mention it. Its one of those things no one told me before I bought my can. Just a FYI, it is almost impossible to find a barrel in 1/2x28 for a Sig 228. The ones that are available go for around $300, and most of them are backlogged for several months...
Good barrel manufacturers seem to be Bar-Sto, Jarvis, and Storm Lake. If you decide on going with a 13.5x1 LH threading, the Sig factory threaded barrel is a very good choice as well.