That's become a hard question for me to answer. Several months ago I bought a Kimber Classic Gold Match. The first two hundred rounds through it was a combination of Corbon, Mullins, and some hardball I picked up at Walmart. I had about four failures to feed. Can't remember which.
Last week I fired almost five hundred rounds through it without cleaning it. Georgia Arms 230 gr Gold Dot, UMC FMJ,
Federal Hydrashok, and Winchester BEB. Not one malfunction.
Yesterday, I fired a hundred rounds of the Georgia Arms Gold Dot. I had one failure to feed on the last round in a magazine. I cleared the weapon, reloaded the round in the magazine, and fired it. The slide did not lock back. Upon examining the magazine I found that a bit of sand had prevented the follower from moving all the way to engage the catch. Conclusion-dropping the magazine in a previous string and then reloading it had resulted in a fouled magazine. I need to buy more magazine so when I practice I don't have to worry about cleaning magazines at the range.
After this happened, I decided to practice malfunction clearing as it has been a while and I have never practiced this enough anyway. I loaded an empty case in each of three magazines. The Kimber fed each empty case. I'm beginning to have a lot of confidence in this firearm.