Have the one from Kuryakin. Easy install, looks and works great. No more taking off gloves and digging for keys. Love it.

First thing i did when i got my bike....no more key

+1 on this question.

I have the locking push button. One of the first mods I did. I have never locked it. Sometimes it can be a PITA to push the center especially in cold weather. I may switch it out to the button only.
Note to anyone who looses/forgets their key. The barrel on most ball point pens is the right size and will unlock the lid.

I put a push button smooth on mine. I like it.

I have the push button locking one too.I agree with the prev poster about it being a little difficult in chilly weather.But I'll be picking up a smooth one because mine just quit working.Tried lubing it but no success.Four yrs old and 50,000miles.Good excuse to get a new smooth one.

Push button only, what a great mod. Security? Not many bikes have locking gas caps so I'm not too worried.

Smooth push button is the way to go in my opinion...the lockable pushbutton is somewhat problematic IMO...B

Smooth push button here too. Had it about a year now and can't believe I waited so long to get it. Looks good and functions with or without winter gloves. As stated lube it every so often; which reminds me...

I've had the non-locking style on every Ultra I've owned, and like the look and ease of use. Some say should be able to lock it, but there are a zillion cars, truck, SUV's and other motorcycles with non-locking doors or caps, so why single out a Harley as needing one.