Completely at risk of outing my identity here given the rareness of the name, but hey ho...
My dad's name is Reynold. Absolutely everyone calls him Ren.
It's a bit confusing when having to give his name. It often gets written as 'Len' and those that don't do that write it as 'Wren'.
Other than that, I think it's a great name but obviously I'm biased!