Blue. I am open to counter information that can be independently confirmed. I have tested 3 CDIs (stock, blue, orange) just as the Admin (Brent) @ 49cc scoot did. My findings matched his in independent testing. I have not tested one of the adjustable that you currently have installed on your scooter.
Perhaps you could perform the same testing as Brent & I on both the orange one you say performs better and the adjustable and share your results.
For those that want to read the testing and method, here is a link to the page it is on (post #13):
http://49ccscoot.proboards.com/threa...grades?page=10