First burn is nice. PIs start a little high but taper down nicely. PIFs look great.
Second burn...not so nice...looks like a coaster to me. Way high PIFs and PIs.
What burn speed did you do these at? My guess is the first was 4x and the second at 8x. Ask yourself, "What else did I do differently between burns to get such opposite results with the same MID?". Could also be poor media in variable qualities.