I bought my first handgun, a 9mm, in 1988. Winchester White Box 115 FMJ was the best deal on the shelf and thought I should be good with that. Sometime in the early 90s I discovered that "magical bullet" called the Hydra-Shok and bought a box. I had a mag loaded with it in the night stand in case things got bad but never fired a single round to test the gun.
Sometime after the the evil Black Talon came along and out went the Hydra-Shok. Then I switched to 45ACP and had Golden Sabers in it. This time I got a good deal on a bunch and ran them in a 1911 without an issue.
In 2010 I went back to 9mm and picked up the 124+P Gold Dot and have been carrying it ever since. I made that decision based on reading what DocGKR wrote, price and availability, and how well it functioned in my pistol.
-Seconds Count. Misses Don't-
Just switched to 9 a year or so ago. Did some study through Youtube and Lucky Gunner's gel tests. The one 9mm I'd had was subcompact, and I ran standard pressure 124 gr Golden Sabre in it for years. Picked up a pile of them for cheap about ten years ago.
Another 3" gun I acquired, that is pretty much never carried, it loaded with 115 gr Gold Dot.
Night stand gun has some 147 gr Winchester Defend in it right now. It was a novel theory, and there's some good test results on it, but I've decided when it's time to change out and I have no more of it, that pistol will swap to 124 gr HST.
My carry gun and backup (M9 and 92 compact) started out with the same 124 gr HST in them. However, I shoot the M9 a lot, and being loaded and unloaded regularly, I was having the top round in the mag set back pretty quickly (I don't bother with +1 on anything over about a 12 round capacity, why chase a loose round all over?). So I got to thinking, long ago I carried the green/white box Remington 115 gr JHP before Golden Sabres came along. I still have a bunch. And his testing may not be scientific, Paul Harrel's results, mixed with my own testing, the fact I am more likely to dispatch a four legged vermin than two legged, and they don't have the frequency of slugs setting back in the case as HST's do. So I switched to carrying them the vast majority of the time just banging around out here in the sticks. I'd probably move to a 124, if they had it.
Practice ammo? I prefer 124 in a lot of ways, but I've got four or five loads I prefer to buy when ordering ammo. Since they're not always in stock, I'll usually buy whatever weight is in stock, and if 115 is cheaper by more than a couple bucks a case, I'll go that route.
So ultimately as long as it's on the list you just pick which works best for you.
I'm still satisfied with the 124 grain gold dots and I'm still willing to take Cornered Cat's word for it.