Thanks for the replies, everyone. They've been very helpful.

Sorry I got wordy back there - to distill it down to the essentials (and you addressed many of my queries already):

I'm considering LW Commanders. I don't like the looks of the E-Series, so I wouldn't buy one unless I fall in love with the bobtail and/or unless they have some great advantages over the older models. (you all address this point well - thanks!)

I guess my main unanswered question is this:
Are there any significant differences between 1)the old/large roll mark 1911Sc, 2) the small roll mark 1911sc, and 3) the 1911pd, or are all three essentially the same?

Is the small roll mark 1911sc the only S&W option that came in all stainless/silver?(not a big deal, but I'm curious).

Thanks for the tip on the Ruger LW Commander as well. I was aware of it, but hadn't looked closely at it yet.