Is the benefit just to swap to a different weapon that have different specialties or damage types or does this have a hidden benefit?  Does a weapon you have in a slot but not equipped possibly add any benefits?   Or no?  To illustrate does a weapon that gives +2 to CON only give that when equipped or does it grant anything when not equipped but in a weapon slot?  Thanks

You only get the benefit when its equipped. Swapping weapons is to allow the player to switch to a weapon that can get through DR the enemy is weak to more than on the previous weapon or to get to a unique benefit the other weapon doesnt have. Also there is one build with Island Aumaua and Arms Bearer and Quick Switch,  where you equip 3 or 4 guns and can spam multiple gun shots without reloading. 

Edited December 9, 20196 yr by draego

Correct. Weapon sets do nothing when they are not your active set at the moment. It's like they are in the stash then.

One obvious use of multiple weapon sets is to skip reloading, but the general idea is to be flexible. Besides that switching to an appropriate weapon in regards to enemies' DR is often better than using Vulnerable Attack and such - it's also useful to keep a backup weapon for more reach or range should there be a situation where you can't touch the enemy otherwise. 

And that's is basically. 

Island Aumaua with four guns, Quick Switch and Coil of Resourcefulness (=zero switch time) can be preeetty devastating.

It probably helps more (aside from the 4x gun) when you know the meta game of what weapons are available.  Even just knowing or paying attention to DR of enemies I suppose it might help more than the feat that gives you reduced attack speed with DR reduction?

Yes, it's more micromanagement but in most cases it's better to switch instead of using Vulnerable Attack (or Penetrating Shot).