Surprised me a bit. The 635 has a 10.5" barrel and think(been awhile) it was an A2 type comp versus the 14.5"+Phantom(not much of a comp) and various 16" pencils + A2 comps (the same furniture/basic external feature layout on all variants) I have tried and the difference was notable in the 9mm versus 5.56. Not saying the 9mm was uncontrollable or painful(it is a 6lbs 9mm after all), but there was more flip with it. I assume this is a variation of the factors in play when a pistol with fixed sights will typically have a higher point of impact when using a heavier bullet weight than a lighter one.

The 10mm seems sort of interesting for hunting because of the increase in power, but very much doubt it would have anything going for it over a 5.56 with any decent for task bullet beyond beating a bore diameter regulation and perhaps a bit lower muzzle blast level which I forgot to mention as a plus with the other 2 pistol chamberings.

"My message to my troops is if you see anybody carrying a gun on the streets of Milwaukee, we'll put them on the ground, take the gun away and then decide whether you have a right to carry it." - Milwaukee Police Chief Ed Flynn