In my 37, I had Glockmeister--local to me--install the extended mag release that's stock in the 35. It was $3-something. When one has time, the original release button is plenty OK, but when I'm shooting USPSA competition and already nervous and pressured, the longer one is LOTS easier to get my thumb on.
The standard (extended) slidestoplever
* works finely in my 37.
* I presume that's what you're talking about. The slidelock is what one pushes down on both sides to allow the slide to be removed. See http://www.lonewolfdist.com/schematicslist.aspx
An EDC S&W M&P .45ACP. A dozen Glocks sold. NRA life member.
"If lethal force is warranted and appropriate under the circumstances, the" (defender) "must shoot until the threat ceases." Pinizzotto, Kern, and Davis, FBI Academy.