This discussion is interesting to me as my 2.0 Compact 9 with 4 inch barrel also shoots low if I line the three dots up. I've never tried firing from a rest but standing with a two handed grip it's consistently a couple inches low at 10 yards. I usually shoot 115 grs but tried 124's as well without any noticeable difference. I've never tried 147's.

Since the Compact is my carry gun it's the one I shoot the most anytime I go to the range and what I've done to correct the problem is gotten into the habit of making a small triangle with the sights with the front dot just above the rear two. I do that all the time so it's become habit. Yesterday I was shooting at 25 yards instead of my usual 10 and was happy to see that my triangle sighting was still putting rounds where they should be at the longer distance.

I've started reloading and have noticed that I get tighter groups with my reloads (115 grs), but I still need to do the triangle sighting to put the rounds high enough.