I am also a Garmin only person. I have a Nuvi on the dashboard and a Geko 301, GPSMAP 60CSx for the trail.

I'm seriously looking at the Foretrex 401 but I need to find out more details. It's small, lightweight and with the high sensitivity receiver should be a great addition. I'll use this on my bike rather than having the Geko attached to my handlebars. It should do all you need.
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Better is the Enemy of Good Enough.
Okay, what’s your point??