Top bottom, and left and right of the circle on the most outer part, then when you look at the orbital oval around the S and the curves on the stroke around the S they also seem a bit pixelated.
Edit: My advice to you -- Don't use stroke (assuming you're using Photoshop), it's good in some cases, but almost in any case there's a way around it. I know when people first start out that just go crazy on the outer glow and stroke all the time because they haven't learned much of it's other features yet, and it's the coolest thing to them, but stroke does not create a perfect representation of the image it's outlining. The farther you draw out, the more pixels it has to interpret as to whether or not it counts as part of the stroke because the perimeter (number of pixels around the actual image increases). Don't use stroke...
It's interpretation, I know you can get the same effect by placing an image behind the shine layers and changing it's layer mode to perhaps overlay and lowering the opacity, then doing some warp effects over it to get it to mold to the curvature of the inner orb itself.
