Or possibly wait for the soon to be released R9 from YHM. It does have some barrel length restrictions so you would have to use it on your 16 incher and leave the turbo K on your shorter barrels. Being a 9mm bore it should be lower backpressure, allow you to run it on your current 16 in host, any .30 bore host you might pick up down the road in addition to 9mm ones. Think of it as a 9mm subgun can that happens to pull double duty as a centerfire rifle K can. You might want a suppressed PCC or handgun in your future. It along with the Wolfman, Omega 36 etc.. gives you options. YHM is releasing their all Ti Nitro 2 later in the year as well. Might be worth a look.
I know you said you only have 5.56 mm at the moment but that might change. If your serious about not getting another K can and I can understand that I think the Resonator would be your better bet. I recently jailed the R2 version. I'm very pleased with it. If your willing to spend considerably more which it sounds like you might since you mentioned Surefire I think you would do far better looking elsewhere. Dead Air's Nomad, Rugged's Radiant, Sico Omega etc.... would be money way better spent.