I've owned two 10mm never had any issue's finding ammo. The only issue is the 10mm factory loads are loaded to what is known as FBI Load Specs. The ballistics are almost identical to a 40 S&W. The 40 actually came to be because the FBI agents weren't passing there shooting tests due to the high recoil the 10mm produced. So they produced 10mm's with less powder. The were then able to pass the tests but there was no need for the larger casings so the reduced overall shell length and now you have the 40 S&W. So unless you are able to purchase true 10mm loads you might as well go with the 40.