also the 305 will show you maps and allow you to navigate to waypoints that you have marked.
I use this a lot as I run mainly off road and am always trying out new routes. For me the 405 had worse funtionality and cost more which is why I went 305. I like the 310 but it;s overpriced at the minute.
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muddy_runner
will have a look at other places maybe Likeys or Pete Bland.
