Have purchased my TTS MT from Herko. Great to deal with, most highly recommend.
I've also added o2's to my '06 FLHRI as well as tuning it myself as an '07 with o2's for closed loop operation.
IMHO, I feel that the TTS tune is at least 70% better then a stock tune. So if I've got another 30% to go, then a stock tune right off the dealerships floor must be in the negative numbers? And many ride with them for a long time. Heat, popping, back fires, heat management issues, and other issues to numerous to list.
I would not be discouraged by how close to a dyno tune that you can or not get.
You can get very close and I'm sure all the percentals are purely subjective, but if you had a tuner with a dyno you would get the the very best tune.
IMHO I bought this TTS MT for my bike to do many mod's myself. So I would not have to get a good street-able tune from a dyno and have to pay for the tune over and over. I feel that TTS MT has done it very well with my first tuning, and I'm not a tuner.
I don't have the excess heat, back firing, or missing. My mileage has increased to higher then 27 mpg, to what I'm not exactly sure this moment. But estimate its over 37 mpg. And the seat of the pants tq has increased a quite a bit over what it was stock. Its really running great IMO.
And if you do choose to do all yourself you have quite a reference library right here as well as a number of other forums. (but a lot of these members as myself frequent more than this one so you may see them around with the same name at the other sites)
More food for thought.
Best of luck with your choice.
Gary