No disrespect intended, psword. Everyone has different preferences and inclinations, and if you're used to pocket-carrying an MK9, any imaginable iteration of an R9 would definitely weigh less!
I've owned two MK9s, and never found them good choices for pocket carry in my own case; felt like a brick in the pocket. What sort of pants do you wear?
None of the 9mm loads I mentioned in my post above were intended to be thought of as "short barrel" loads; I merely meant to indicate my preferences in 9mm cartridges for use in standard size, robust modern 9mm pistols, eg, Glock 19, HK P7M8.
Interestingly, Double Tap achieves "+P" velocities in much of their ammo line without +P detonation pressures, hence said ammunition has no "+P" headstamp mark, yet is clearly very "hot", and moreso than many +P-marked premium cartridges, in .45ACP, from Winchester, Speer and Federal.
Their 9mm ammunition IS marked "+P", however.
(But even if they somehow manage to come out with a 9mm round not marked or rated "+P" at some time in the future, I'd be very leery of shooting it in the R-9S!)
As experience teaches, TANSTAAFL, and trying to get extra velocity from guns with shorter barrels usually requires extra powder, with correspondingly-increased muzzle blast and flash, not to mention increased wear to the gun compared to standard loads.
The R-9s does fine for my purposes with standard 124gr Gold Dot JHP.