Well Gene, I want them black because I think they look like $hit the way they are now. I have a high grade gun with an engraved hanger and it would simply look better without plastic looking choke tubes. BTW, you can also coat the threads, as it can be applied as thin as .25 mils. This isn't the stuff you buy in a spray can. It's ceramic based, applied with an airbrush and baked in an oven.
Either way. If you have a good airbrush (not a cheap one with the little compressed air cans used for model makers), you can buy the material from Brownells and then bake it in the oven. Don't quote me, but it's something like 250 degrees for 3 hours. There are also services that do this. It's the most durable coating on the market. A lot of rifle and pistol shooters have it done and those in humid climate have it done. I'm just trying to get some feedback on it's application on titanium and on coke tubes in particular. For instance, I'm not sure if a choke tube wrench will mar the finish or not.
Don't do the threads. I had my Ljutic barrel Cerakoted, and they coated the lug as well. Had to remove it as the tolerances are way too tight in the lock-up area. I suspect there is no good reason to also do the choke threads if its simply a cosmetic matter. It is very durable.