I got myself an M305 last year, and I was very excited when I did. They're a beautiful looking rifle, nice sights, lots of mounting options, good calibre, etc. Mine was particularly well fitted, with the trigger group and gas system all very tight. I was hype.
...Until I examined the mechanism. I already knew the bolt was open-topped, which is meh, but not that unusual for rifles of the time. But the oprod looked flimsily designed, in that it's offset in two directions. (In other short stroke designs- T97, SKS, vz58, FAL, etc, everything is nice and linear.) I guess I knew about that too somewhat, but that's quite different from seeing it in person and how it all "fits" together. It struck me as something that could conceivably all pop apart if the stars were to align, and there are reports on this forum of it happening on occasion. That offset oprod interfaces with a roller and tracks that are wholly exposed to the elements, as are the tracks the bolt rides on, and there are wide gaps in the receiver that would make it easy for debris to get into everything, and hard for it to get out. My initial reaction to the mechanism was "this would be utterly unreliable in less than pristine conditions."
And it appeared my suspicions were correct-
https://www.full30.com/video/9eef6b3a4eb6c8846a4c8dc4b8968bc4
I also found all the typical things. It's very ammo sensitive, some quality ammo would group acceptably, others would give me a shotgun pattern. They need some work to be accurate. (I went and replaced a bunch of recommended parts and the groups did tighten noticeably for the ammo that shot well) Strip and assembly can cause POI shifts and you have to re-zero. I sold mine rather quickly after concluding much of the hype surrounding the rifle was just that.
Now don't get me wrong. They are VERY nice looking rifles, they are just gorgeous, particularly in wood. They CAN be very accurate, with work and if you pamper it. They're affordable, they shoot .308, which is everywhere and there's tons of options for. The recoil is very soft for a .308. These can be fantastic target and hunting rifles, and a fun project gun for those looking for that - someone who likes to be really invested in all the little tweaks and tricks.
In the 1930s, yes, the M1 was a top of the line, acceptably reliable rifle,
compared to other semiautomatic rifles of that time. But that time ended, and to keep using that design post-war was, I think, negligent. There were legitimate reasons the M14 was swiftly replaced- it was the second shortest serving rifle in US military history- and anyone who holds it up as an old-school, wood-and-steel, utterly reliable legend needs to maybe take a closer look at it.