Read this about ignitions is my best advice. I won't give an opinion on a TC ignition seeing I've done little research on them.
http://www.mikuni.com/pg_ignition.html My Evo is a stage 3. Wisco 10:1, Crane H-286-2B advanced. My carb mod, and cycle shack staggered duals. My wrench used a thinner head gasket to lower the squash and then a thicker base gasket to keep the piston travel to keep the 10:1. He uses Cometic race gaskets, the only way to go.
I get 45-48 on interstate running 65-70 depending on the wind. And 52- 55 on secondary roads depending on wind and hills going 55- 60. I've seen as low as 38 pulling my trailer two up on interstate and as high as 42. It all depends on wind and hills. I've got as low as 45 on secondary pulling my trailer 2 up and as high as 50. Once again, hills and wind plays a factor.
The dyno jet kit is a needle change with options for shimming the needle. It also drills the slide and uses a lighter spring. It changes the emulsion tube to use its personal jet. The emulsion tube has fewer air holes in it so it makes the air fuel mixture richer by taking air from the mixture. It works, its just not economical for what it does when my mod does the same thing and is less, and gets better mileage. I did a throttle up when i was still stage 1 with a stage 1 Custom Softail. Dyno jet kit, I got a bit of a jump on him and kept that 1/2 bike lead. I can't remember what it was because it was years ago, after talking he said his mileage was not quit as good as mine.
I told you 1996 because if you go to the parts man and ask for a sportster 1200 needle they will ask you what year. They never changed them they are all the same. So just ask for the 1996 that's what I do.
If you can do your own carb mod, do mine. If you want to make your wallet lighter by using they dyno jet kit go for it. I assure you your seat of the pants will not feel or see the dyno jet kit as being better! You shim the needle to much and you will feel your wallet get lighter at the gas pump.