As far as I understand they are the same coils. I.E. specs they are manufactured.
I have the original donut 8 that came on my bandido II micromax and my Cutlass micromax and they perform the same as the white 8" do ut that cam on my outlaw.
However as far as the epoxy they use to fill them and how your original was taken care of and stored, you may see that it works better if the original isn't in good condition.
The only time I saw a coil that didn't work as intended was when I first got my Troy shadow x2. It looked perfect. Seemed to work perfect on my analog Tesoros. The only time I noticed oddness was with my Deleon.
Started getting funky screen reading on the display. So, I sent both the Deleon and the shadow into Tesoro. Originally I thought the Deleon needed to be tuned to the coil because it originally has the 9x8 spoke coil. When they contacted me they said the coil was bad/out of tune. They rebuilt it and tuned the Deleon to it. Now they are a match made in heaven.
Only point of the story is that older coils only don't function as well as the "new" ones when they are broken lol. My donut from the bandido II micromax and the Cutlass micromax (oldest I have) function perfectly.