What advantage do the stair keys give?

[SandWitcherOnRye]

Because the stairs are so close to the elevators on each floor, they don't seem to be useful in escaping (at least from what I've seen ~30% in -- if you're by the stairs, you seem to always have a clear shot at the elevator)

Do they minimize the noise you make when changing floors, delaying Jimmy being able to locate your floor?

[Stigma]

Quite frankly, I almost never used the stairs, that would be a hassle since I only had one stair key. The number of stair keys you get seems to be random.
But I'm pretty sure Jimmy hears the racket when you use the elevators. I cannot tell you how many times I saw him right outside the elevator doors after going inside. Thus, he obviously hears it.
One thing I noticed, and this is just a calculated guess, is that Jimmy cannot ambush you during the animation sequence when you're waiting for the elevator.. At times, he was most certainly no more than five feet behind me. It certainly is tense when you've just spotted him while waiting for the elevator, but since he (probably) cannot touch you at that specific moment, it's either a bug or it's simply designed to stress you out.

[PhantomX]

I tried using the stairs but the only thing is when you unlock them Jimmy decides to lock them again. so whats the point?, elevator quicker anyway.

[Baggy Cat Entertainment]

He doesn't always lock them, only when he's whacked you and then only sometimes.

[PhantomX]

my last game play was on extreme no whacks to the head but yet the 3rd door was locked when I clearly unlocked it, so that was a sometime occasion lol. (my luck) great game though. I'm on my 5th run to get the last of the trophies. I want a sequel definitely!!

[Gibble]

I'd heard it delayed him appearing on the next floor but I have no idea if that's actually true.