Base model Fenix 5. I pretty much agree with what HB says. Just minor disagreement on opinion in that I don't care to look down while descending anyway, so being wrist mounted doesn't matter. I ride 95% by feel, even though I track heart rate and power on everything (all my bikes have power now).
Wrist optical HR is hit or miss. For some it works, some it doesn't. For me it's meh. It records close enough for hand grenades. But I mostly use it for tracking purposes. If I want accurate HR data, I wear my strap. I'm always recording power. Battery life was a huge selling point for me.
Before this I had one of the Vivo's (forgot which). Honestly, it worked great for 90% of my riding. But it doesn't record power (which at the time I only had power on my roadie), and battery life was only okay, but handled most of my riding still (7 or so hours). I have it to my now ex GF and the optical HR works great on her wrist.
I'm not an Apple person. But, if you are, if definitely keep those watches as an option. Just because of how the Apple ecosystem works, it's sure to be pretty good. But...I don't like Apple...
I use a bar mounted Garmin when I need easy to view navigation. Otherwise, I use the watch for everything.