I've no personal experience of them, they certainly get generally favourable write ups, though I have reservations about the amount of coverage they really provide. I expect the seatpost is still going to cop a lot of muck for a start and any water bottles you have in the main triangle will get pretty mucky. I do like the look of the mounting system a lot though, easily removable without using throw away cable ties.
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I use a Mudhugger gravel fender on my bike, not the prettiest of things, but due to the size of my tires, I can't fit a traditional mudguard in there.
Personally, if this mudguard had the mounting system of the Win Wing, then that would be my personal favourite, I really hate the wasteful cable tie's I need to use to mount the mudguard.
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