I have shot both extensively for over 40yrs, and seen quite a few examples of both types of guns give problems, and examples of both types of guns that practically never had a failure.
Many of the revolvers that gave problems, came from the factory with quality control issues, but a top quality revolver, once thoroughly vetted, and the possibility of factory defects eliminated, usually proved to be very very reliable, and would then only display a problem due usually to ammo issues, with high primers being one of the most common problems seen. And that problem can be eliminated by checking all of you carry ammo before depending on it. This is done by actually loading every single round in the cylinder of said gun and then spin the cylinder in the gun to see if any high primer issues show up.
Lint or dirt, or unfired powder granules getting under the extractor plate will be the next most common failure. But load a proven revolver with good ammo, and give the cylinder a spin to eliminate the question of a high primer, then put it in you holster and you will probably have a gun that is pretty much 100% reliable at least for the first 6 rounds in the cylinder.
The 1911 can also be extremely reliable, and the gun I usually trust my life with, but I have seen plenty of issues with them over the years. One problem with 1911's is there are so dammed many people making them and many to a price point. If the gun was built right, and has been supplied with proven magazines then it's pretty darned reliable. However, I have seen magazines go bad, and that is usually not evident until you experience a stoppage, and some brands of ammo don't always work in some guns.
Some guns are more ammo sensitive them others, but the 1911 does usually handle high primer issues a little better then a revolver and the 1911 will be easier to clear if a problem there does develop, where a revolver will often lock up, but like I said the revolver can be checked ahead of time for high primers, although I have seen primers back out after being fired and start dragging on the recoil plate of the revolver, but usually not to the extent that a stoppage develops but it could happen, however remote.
The other potential problem which could develop in an otherwise proven 1911, is the extractor. I have had this happen a few times on guns that I had trusted for a extended period of time to run 100% previously. I have had the problem develop suddenly on a couple of gun with complete surprise. And once replaced and tuned, returned to 100% reliability. One or two were broken extractors and one I remember just lost it's memory and got out of tune, but it was enough to make an otherwise history of extreme reliability turn to crap on the given gun.
Bottom line is between a good 1911 and a good revolver, I don't seem much difference in reliability if maintained decently. However, if were to start talking about small guns, then I would definitely give the smaller revolvers like the J-frame Smiths the edge on reliability over various small autos. And the smaller autos are harder and usually slower to clear than a 1911 if problems do develop. But we are not talking small auto's here on this thread, but 1911's instead.
My main carry gun is a Colt lightweight Commander and has been for many many years.