Garmin Watch that downloads Daily HR

Not entirely sure this is what you are looking for: you can get all-day HR in the form of FIT files (Monitoring files); either via Connect Web (save daily summary) or directly via USB from the watch. To have a look at the data, you can use the FitCSV utility (from the FIT SDK; https://www.thisisant.com/developer/resources/downloads/) Monitoring files are a hassle to parse though (in my humble opinion). This works for any Garmin that has activity tracking - although monitoring files may be deleted from the watch after syncing, so you'd have to get them via Connect Web in that case.

Thanks I have the Utility, but how do I execute/use it?

For example unzip the SDK in /user/yourname/fitsdk/, make sure you have java installed, then:

java -jar /user/yourname/fitsdk/java/FitCSVTool.jar -b [fit filename] output.csv

It takes a bit of programming to get meaningful data out of it. It is easy to filter the HR data out of it, but not easy to get the correct date/time linked to the HR samples. But things like these are not discussed on this forum, only watch software development (Connect IQ) is discussed in the developer section.

There are still some spreadsheet analysis you can do though, like min, max and average HR calculation per 24 hours.