Tune Options (Besides Dyno)

I was wondering what options are out there right now for getting a tune.
There are no shops around me that have any experience tuning the LSA engine and I would not have confidence in letting them tune my car on their dyno. I previously owned a Trail Blazer SS , and had some minor issues when I had my TB dyno tuned.

So that more or less limits me to handheld email tune or having a (ECM?) tuned or pre-loaded(?) and sent to me?

I want something that I am able to swap out and go back to stock if needed.
What if any vendors offer hand held tunes?

With just a board swap , would it not more or less just be a generic tune that wouldn't be able to be adjusted at all? I do not know much about this , but a preloaded tune would not be able to account for the current DA the car is running in and other unique factors that vary from stock car to car?

The only thing that scares me about a handheld , is that I have read some things that it may cause some issues if it does not have the correct firmware etc. I also would not want it where if I had any warranty issues , GM could see that there have been changes made from the factory settings even if you remove the custom tune you used from your handheld.


Sorry for the long winded post , more or less looking for any and all options I have for a tune besides a dyno tune and what is recommended. Ability ot go back ot stock is very important for me.