I've been playing slide for 30 years on my ring finger. There's no specific rationale for why I started on the ring finger, other than it felt the most natural when I first started.
Over the years I've tried to switch to the pinky finger a few times, just so that I could chord better with the other three fingers... but I've never been able to make the switch. I've even stuck with it for months at a time, only to have a gig with a song that required slide, and I couldn't get it all together for gig... so I just stuck it back on my ring finger.
I almost always play in standard tuning (sometimes I lower the A string to G, for a modified open G), and my slide style most resembles Billy Gibbons or Joe Walsh.
Over the years I've tried to switch to the pinky finger a few times, just so that I could chord better with the other three fingers... but I've never been able to make the switch. I've even stuck with it for months at a time, only to have a gig with a song that required slide, and I couldn't get it all together for gig... so I just stuck it back on my ring finger.
I almost always play in standard tuning (sometimes I lower the A string to G, for a modified open G), and my slide style most resembles Billy Gibbons or Joe Walsh.