I think if you are planning on using your R9 like a compact or larger model, it might not be the best choice in your situation. Facing the need for fast magazine change is probably in the wheelhouse of a larger pistol. The heel magazine release is a lot safer for deep pocket carry, where the chance of the release activating is lessened. That is how I carry mine, even when carrying a larger handgun.
Once upon a time I shot quite a few competitions at the start of IPSC. Quick draw, fast shooting and blazing magazine changes were name of the game. In no way does the Rohrbaugh fit that slot, IMHO. You might look at the newer generation of small pistols like the FN Reflex (really good triggers out of the box), Springfield Hellcat, and the fan bois favorite Sig P365 in its various flavors. These are all feature loaded, have that traditional American magazine release, decent capacity and carry really nicely in a belt based holster.
I don't have an issue switching between guns as I try to stay competent on most all my firearms, no issues with the bottom release on the old H&K squeeze cocker which I still carry on rare occasions.
Just my thoughts..............
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