Welcome to CPF!
SureFire offers the KT2-BK TurboHead kit for the 9P.
I understand it currently comes with the MN15 Lamp Assembly (rather than the N2).
The difference the 2.5" diameter reflector makes over the standard 1" diameter reflector is significant.
The beam is far more narrow and concentrated - the intense light is able to illuminate targets further away far better compared to the standard bezel.
I don't think the V16 leather holster (open-topped) is suitable for the 9P+KT2 for the reason you mention - it will force the TurboHead to be too close to your body, especially if you wear body armour... That said, your V16 on your duty belt may afford sufficient clearance. Its difficult to say.
This is what the 9P+KT2 looks like (actually this is a 6P+A19 body extender to make a 9P but you get the idea)
This is it inside an "SureFire M6 pouch belt pouch":
John Willis of the Real SOE is the man to go to for an M6 pouch.
This is a beamshot of an M3:
This is the MN11 High Output Lamp Assembly (225 lumens / 20 minutes).
This is a beamshot of an M3T:
This is the MN16 High Output Lamp Assembly (225 lumens / 20 minutes).
Although the 9P's P91 Lamp Assembly produces a less intense white beam compared to the M3's MN11 Lamp, the M3T's beam is the same as the KT2's beam and the two beamshots give a good sense of the difference between the standard and the TurboHead bezels.
You ask whether the KT2 is worth it. If you are finding that you would like to see more clearly things that are further away more often than you use the flashlight for looking at things indoors then I would suggest that a TurboHead (or a larger diameter flashlight in general) is a better option.
If you need to rely on your flashlights for your job then perhaps a different approach may suit your requirements better... For example, a TurboHead flashlight (such as the M3T), or a larger dutylight (such as the TigerLight 8" FBOP), and a smaller two-SF123A flashlight such as an E2e or G2 etc for times when the larger more powerful light is inappropriate.
I personally find the TurboHead flashlights more useful compared to the standard flashlights when I'm using flashlights outdoors.
I hope you find this useful?
Best regards,
Al