A perfectly good burn. Low PIF numbers show that there are few large-scale (millimeters-long) error burts.
There are a couple of spots around 3.8 GB that might be noteceable as very small darker dots or narrow shaded areas on the recording surface. If you want to try spotting them, look at the purple recording surface under a bright halogen light source, from an angle at which the dye appears to be of the lightest shade. Rotate the disc, and look for small dark spots about 4.5-5 mm from the edge.
Elevated PIE numbers in the first half of the disc indicate the presence of shorter error burts (but nothing that would overwhelm the inner Reed-Solomon code's correcting capability). They could be caused by slightly incorrect laser power applied in the 4x and 6x zones, or slightly uneven radial dye density.
That would be my theory, based on the scan I see.
Either way, a good burn, and definitely nothing to worry about.