If you care about sensor connections I'd recommend going with the F5+. I could make the F5S+ loose signal from Stryd when holding hand on the bezel for few seconds (similar to what my old F5 did), while on F5+ I can't make the connection drop even if I cover the watch for several minutes. HRM-Tri also had several second gaps with RD data even when there were no obstructions. The HRM-Tri actually worked better even with my old F5 than with the F5S+.
I admit the F5S+ is much better looking though as it comes with much less bezel, if you can first fit it on your wrist (the starp is much shorter and has only one retaining loop). Still I would've actually preferred the F5S+ otherwise, but end of the day I couldn't justify living yet again with a watch that drops connections so easily.
Interesting, I have both Stryd and the band and I have not experienced any drop.
I do agree with the starp though. However I have bougth a few from Amazon that are very nice and cost less than 10 quids.
I have some of the Apple type straps for my 645 and love them. So far though I’ve only been able to find them for the 5X.
Can I get a link to one of your Apple watch like straps?