These are my photos of my watches, starting from oldest to newest. These are strictly IWC; I will do IWC Porsche Design later if anyone is interested ...
I picked up a titanium Aquatimer Chrono (3719) just like yours a few months ago, and have been on the hunt for velcro strap (and endlinks). Seems like you've enjoyed that combo?
Frankly, it’s not a very good solution for the GST models that I now own. It’s better on the smaller and lighter GST watches. Otherwise to keep the watch from moving around too much, you have to put it on very tightly.
I think of my titanium Aquatimer as 'lighter' but not 'smaller'! I really like it on the bracelet, less so on the rubber, so I've been hoping to find the velcro to pick up the slack.
This strap has SS end fittings, but they work fine on the titanium watches. The 2000M watch was about the limit for me. I should check and see how many GSTs I still have that can use this strap option. I seem to have lost or sold the rubber strap.