Now I use this:
I'm getting 22 hours on a charge. This will keep me through racing season this year. It's reliable, and I'm now using it every day. I've gotten the watch to hold a charge for about 4 days. There's a magic "sniff" setting that makes all the difference.
Now I'm working towards a keychain sized receiver that will use BLE to send packets to the watch. All the pieces are there, I just need the time to put it all together.
That's hard now that the weather is decent again.