Have you run the Gami lean test yet? If not, do that first.
Gami Lean Test
I have the prototype XP-400SRE in my Lancair. Just installed the new sump a few weeks ago. I ran the Gami lean test just the other day and found that all 4 cylinders peaked at less than .1 gph difference in fuel flow. That is WAY better than most of the graphs Gami shows on their site.