I've got both. All by itself a reshaped safety button head ain't going to make much of a difference. I don't like the one in the picture because in addition to reshaping the side profile, (Which gives the most improvement.) the head's flat profile has, also, been reduced in size - Which is not good.
Older Glock striker (FP) safeties are solid steel; newer, 'cost effective' ones are nickel plated. Unless you intend to have the modified part replated (Which CAN be done if you want to go to the trouble of finding a shop.) I'm going to suggest that you leave the newer nickel plated safety buttons alone.
Besides, the new longer steeper, 'sear kick-plate' angle on Glock's most recent trigger bars makes cleaning up and smoothing out a Glock trigger's, 'let-off' a lot tougher. I've got two older (low serial number) third generation G-21's that have genuinely nice reworked and polished, but entirely stock, triggers in them.
However, I can't get the, 'let-off' on my newer (higher serial number) third generation G-19, with the newest version trigger bar inside, to be anywhere near as smooth and light. On the plus side, though, the newer G-19's, 'Safe-Action' is much less likely to, 'stack' than any of the older trigger bars I've worked on.
Nowadays, if you want a better trigger on a Glock you've got to think Vanek! http://www.vanekcustom.com/3.html