I have shot the turkey thug version for a few years now, did well with the factory tube which is supposed to be like a .580 from what I have heard, bought a Indian Creek .555 and it is pure evil, however the tube is getting gouges in the wad catchers, checked with Indian Creek and they said it was normal.
I assume at some point it would have an effect on the patterns but does not seem to at this point!
Happy those 8.5 look wicked, I was looking at that choke recently.