I have both. I like my key better. In my dorm we have a key card to get into the dorm and then a key to get into my room. the problem with key cards is they are faulty. I'm on my second key card, the one they gave me the micro chip was able to almost completely pop out of the frame. now it appears that about half of everyone is having getting the door open to the dorm it just flashes a yellow light at me, then I am reduced to banging on the door until someone lets me.

my key has never failed to work, I lost it once, but it never did not open my door. I want to stick to my keys.