Welcome, chameleon,
"This is a great site,"
I couldn't agree more. There's a lot of good and experienced people here and it's a pleasure to communicate with them.
"...I will do some research here before I actually purchase the Rohrbaugh I want."
I think the main decision by far is whether to get sights or not. I got sights (the R9s) and have no regrets, although I don't always use them.
Unless you really hate having sights on such a pistol, I'd suggest ordering one with sights.
I originally thought I'd probably "melt" the gun and if I didn't like the sights I could file them completelly off at that time. Now, after enjoying the little gun a great deal, I think I probably won't do anything at all to it except enjoy it exactly as it is, which is darned near perfect for an ultra high quality 9mm. pocket piece.
The only other decision is the color of the anodization of the aluminum frame, and frankly, I don't think that matters very much unless you feel really strongly one way or the other about having a dark frame or one that's lighter in color.