You do realize, this ain't the place for a rational opinion on that matter, right? Of course you need to get both. Then get all the different barrel lengths for each variation. Then you need to collect 586s to complement the 686s. And of course you need the Highway Patrolmans. And the 27s. Each dash, each barrel length. Oh, and then there's the variation of stocks...
On the fer real, that looks like some really fun shooting. I personally have a soft spot for the big blued N frames. Shooting bunny fart wadcutters, recoil is so low it almost goes into reverse recoil. The 686 is darn fine to for a working gun. I just don't find the weight difference between an N frame and an L frame to be worth fretting over myself.
Looks like great shooting! I hope ya' get to pick at least one to have some more fun with!