With a fresh battery it works about 75% of the time, but the battery in the fob only seems to last a couple of months at best.  Sometimes it fails, I dig out my key and unlock the door manually, and the contact of the key actuates the lock and re-locks the door before I can get in.  This is particularly annoying because it din't work initially, and I had to use the key.  It also seems to be less reliable in very cold weather.  Overall, I spend a lot of time fumbling for my keys in the rain