SGT Rock is 100% right. The other two were right to point to the wonderful work done by Lucky Gunner on the matter, their testing is the most thorough out there along with Tools&Targets on YouTube.
The only tiny bit I would add to the wonderful advice you have already received is subjective and based on my limited experience/testing. When I owned a 38 special snub, I found that MOST (not all, but MOST) hollows did not offer consistent enough expansion for me to feel comfortable with any of the brands/grain weights I could get my hands on. I really wanted to try the Federal 130g micro HST based on the incredible results Lucky Gunner got with them, unfortunately they were unobtanium the entire time I owned my Model 36. For that reason I eventually settled on the fiocchi wadcutters (I believe 145g) because they were avaliable and my gun was not rated for +P. Now the only Smith I own is my 686-3 snub which is my grail gun and even with 357 magnum and a 2.5¨ barrel I have found some ammo still does not give great expansion, so I imagine even with +P and fast burning powder of short barrel ammo, you would be hard-pressed to find many 38 +P rounds out there that will accomplish the three priorities of defensive ammo IMO:
1. Reliable
2. Accurate
3. Available
The more experience I get, the more I think a majority of ammo is marketing and our doubts get the best of us. The reality is that if you shoot whatever you choose well as SGT Rock said, most ammo will do just fine. I think regular wadcutters would work fine, and buffalo bore is a great company, so if you want those and shoot them well, go with what you trust!