Unless you're riding for 4-5 hours, 10% should still be more than enough to get through a workout though? And in my experience a 10 minute charge would have you north of 30%.
not in my experience. i had an edge 120 bike computer and a vivoactive watch, and the last 10% wasn't enough to get through anything. the 10% from 100 to 90% would be plenty, but the last 10% always drained really quick and charged slow.