I'm in the camp that likes the paddle release. It wouldn't cause me to not buy a gun I otherwise wanted if it was only available with a button, but I'll choose the paddle if it's an option.
I activate it with my middle finger, keeping my trigger finger in index where it belongs. This keeps widely-spread points of contact on the gun in my strong hand grip, even if a slight shift is required, and prevents sweeping across the trigger with the trigger finger between index, releasing the mag, and back to index. Very natural and automatic after awhile.
It's critically important if an HK45c mag release is to be used on a USP frame that it be properly fitted. Did a writeup with pics of how and why a couple years ago.
https://pistol-forum.com/showthread....l=1#post929914