How high is the dot sitting on the slide. Is picking up the sight picture werid?
I actually have it milled to the same depth as a shadow and modified the FPB to still work. Not something we would do on a customer's gun but I'm perfectly comfortable doing it on my personal one.
At any rate, not high at all and I've been shooting pistols with dots for years now, so no problem at all for me as far as sight picture.