beefyz- Welcome to Autopia!
Heh heh, few things get these forums stirred up quite like the topic of leather care!
With 99% or more of auto leather being "coated" in one way or another, most "treatments" are a waste of time ad money and actually attract/retain dirt, and dirt (and the abrasion from it getting rubbed in) is what kills leather IMO. OK, some older leather (e.g., my Jaguar) is different, but that stuff is quite uncommon.
(Note that all but one of my vehicles have leather, so the following covers garage-queens to daily drivers, everything except that old Jag
99% of the time I just wipe my leather interiors down with an Interior Quick Detailer. No conditioning, no "treatments", not even any dedicated Leather Cleaner (though I do have a scad of all those products, they just sit onthe shelf most of the time). With all my leather interiors being pretty old now, I can say with confidence that this minimalist approach works great for me over time and many miles of use. I do something more involved maybe every other year, if that often.
Recommended for when you do need leather products- Leather Masters and Sonus. Recommended HIGHLY- stuff from Leather Doctor. I utterly despise Lexol, hate the stuff...but I'll admit I haven't tried it for a few years and maybe they've changed it. R
emember that bit about leather being coated- most Leather Products only contact the leather by geting through cracks/micro-fissures/worn-through areas/etc. in the coating, otherwise they just sit on top of it (the coating). When those compromises in the coating become more extensive, the rules can change a little and the "conditioning" can be more important and beneficial. But even with my old Tahoe (*really* compromised leather!), I hardly ever need to do much of anything, and people predicted that leather would fail many years ago...hasn't happened yet.