After much research, I've decided to carry Speer Gold Dot in my 9mm M&P Compact, but I'm not sure whether to use 115 or 124 grain (both standard pressure). Are there compelling reasons to choose one over the other?
I know the 124 grain +P is by far the most popular and street proven, but I'm not looking at +P and +P+ loads. I find that with standard pressure, I'm faster with followup shots and a bit more accurate. I'm also a bit wary of carrying 147 grain, due to what I perceive as a greater risk of overpenetration (I live in an apartment and am often out in the city), but I could be convinced otherwise.
In the 115 grain corner, Massad Ayoob in The Gun Digest Book of Combat Handgunnery has recommended the 115 grain Federal 9BP as one of the most real-world proven standard pressure 9mm loads available. I imagine that the 115 grain Gold Dot, with a more reliably expanding bullet than the 9BP and otherwise similar parameters, would perform even better, but that's conjecture on my part...
On the other hand, Dr. Gary Roberts over at FirearmsTactical.com says, "With the exception of the Barnes 115 gr XPB all copper projectile, in general, most 9 mm 115 gr loads have demonstrated greater inconsistency, insufficient penetration, poor intermediate barrier capability, and failure to expand in denim testing than other 9mm bullets. For those individuals wanting to use lighter weight, supersonic 9 mmís, I think a better alternative than the vast majority of 115 gr loads is to use the slightly heavier 124 to 127 gr bullets or the Barnes 115 gr all copper bullet" (Best Choices for Self Defense Ammo). He also specifically lists the 124 grain Gold Dot as a load he recommends.
With all that said, I know that Gold Dots in any variety (and most modern defensive ammo choices) are of sound design and will stop a threat if I get the rounds on target. What I want to know is if there's a compelling reason to choose one over the other, or if debating 115 vs. 124 is basically arguing over how many angels can dance on the head of a pin. Thoughts?