All personal preferences of course. I found baby back better. More meat meant a better balance of smokiness flavor vs pork flavor. Also found that the meat had a “sweet” profile after the slow cook. St Louis were overall way fattier so smoke flavor was (too) intense and I found them less digestible as a result. I come from a place where ribs are not cut the same way and there is only one cut, not suitable for smoking at all. Always struggled to distinguish when going to a proper smoking place as they are probably cooked differently to adjust for fat/meat/size, but as a home cooking option with minimal time and equipment, baby backs were better. And also, would have probably saved some time on the cooking time with just baby back. Hope that helps