There is no substantiated proof that the aluminum doorman cooler will not develop a leak. Nobody had it long enough yet. All assumptions of this failure revolve around the part being made out of plastic.
BTW, aluminum is quite a brittle metal, it may develop cracks from over tightening as well. Again, no real long term experience has been documented yet.
I'm with you on this one. As much as I was a proponent early on of these aluminum replacement units, I'm not so sure anymore.
If you poke around various videos, like motorcitymechanic, even he admits it's impossible to pinpoint the source of the leak on the majority of the plastic OEM assemblies. By the time you get to them, the bases are submersed in oil and you can't run the engine at that point given the whole intake and fuel injection system has to be removed to get to it.
He does claim to have seen leaks from the threaded in sensors and the various glued in place plugs on the plastic units. He also believes the O-rings to be the bulk of the leak sources. The aluminum replacements rely on the same O-rings and the same threaded sensor ports.
I don't know that anyone has ever suffered a cracked unit from the cap being over-tightened, but I've wondered if the movement involved with removing an over-tightened cap moves the sealing surfaces just enough, in combination with those O-rings being cooked flat from heat is the smoking gun.