Today I initiated my new Rohrbaugh R9S Stealth...
Although I found the pistol to be perfectly clean and well lubricated from the factory, I did it again just because that's my usual practice with any new weapon.
I bought two extra magazines right from the get-go, so I have 4 available for shooting. Before leaving the house I loaded up with 6+1 115 grain Gold Dots, and I loaded six rounds of the same ammunition in each of the remaining three magazines. I used two magazines with the factory flat floor plates, one of Yankee2500's straight magazine extensions, and one of his curved magazine extensions.
I went to the local indoor range where I have a membership. All rounds in this shooting session were fired at a distance of 15 feet.
Here is the first target... a full load of six plus one followed by three more magazines of Speer standard pressure 115 grain Gold Dots. I think the gun and ammo are capable of better results than what are shown here. I had some vertical stringing as I got used to the trigger. That having been said, they all went close enough to point of aim that I was pleased with the results.
(Please excuse the poor-quality cell phone photos.)

I had no problem shooting with the flat factory magazine floor plates. The quality of John's magazine extensions is EXCEPTIONAL. However, I found that while the straight magazine extension was comfortable to shoot, the curved one did not fit my hand well and I do not care for it. (I will keep the curved magazine extension to see how my wife likes it.)
I also noticed while shooting/carrying during this brief outing, that there are two sharp points on the forward edge of the factory flat magazine base, where the curved front edge meets up with the straight side edge. This isn't much of a big deal when the magazine is in the pistol, since the thickness of the grips tends to prevent contact with the edge in question to some degree. However, carrying spare magazines is a different matter and I think there is a possibility for this same sharp edge to wear on clothing. I think I will carry my Pup with a standard magazine in place, but use John's straight magazine extensions on my spare mags.
The two magazines I used with standard flat floor plates were the ones with the black finish. I am left-handed and wear a Titanium wedding ring. After my shooting session I noticed the black finish was worn off of the front left corner of both of the black magazine bases. (This is after having fired two full loads through each magazine.) It doesn't bother me all that much, as I'll just touch that area up with a Sharpie after each shooting session. It is noteworthy though, to anyone who tends to get uptight over such things. I got the black magazines to use for carry, just to minimize the visual profile of the gun in the event of a wardrobe malfunction. I like the black finish, but I wish it was more durable.
My first impression during this initial 25 rounds was that although the recoil is there, it is nothing I can't handle and I do not anticipate wanting to own a .380 version of this gun.
Now to try a few other loads and see how they work out...

Next I fired six rounds of Federal standard pressure 124 grain HST. (Upper Shoot-n-See circle, in the center of the target.) I REALLY like this ammo in my Kahr PM9 due to its accuracy and low flash. It seemed to perform equally well in the Rohrbaugh.
I then fired six rounds of Federal standard pressure 124 grain Hydra-Shock. (Lower Shoot-n-See circle, in the belly of the target.) Flash was noticeably greater with this round, and the group was much bigger. I will discontinue shooting this particular load in my Pup.
Next up was six rounds of Federal standard pressure 115 grain hollow point, the "Classic" 9BP load. This was fired using the orange spot in the head of the target as an aiming point. The ammunition was not unpleasant to fire, but it seemed to print to the right of the point of aim. Jury is still out on this one, as I did not shoot enough to determine if it was me or the ammunition. I'll do some follow-up shooting with this load before I write it off...
Lastly, I shot 7 rounds of Winchester White Box 115 grain ball, using the orange circle to the left of the head as an aiming point. The ammo was pleasant to shoot and while the group was not as small as I wanted, it was roughly centered around the point of aim. I was happy this was the case, as I have a lot of this ammunition on hand for practice.

When I got home to clean the pistol, I noticed the outer recoil spring was visibly different from what it had been prior to the shooting session. In the photo below, the original spring is on the top and a new, unused replacement spring is on the bottom. I re-installed the original spring after cleaning the gun. It is my intention to shoot 150 rounds using this spring and then discard it. (This is after considering that I am doing a lot of racking the slide without firing while this spring is installed, part of me familiarizing myself with the weapon.)

BOTTOM LINE: I am a happy camper and I am VERY happy with my new pistol :-)
-Tim