Honestly, I have only 1 champ that I swap gear with and that's Starsage. I have a PvP and a PvE gear set for him but it drives me nuts because I often find out that I have the wrong gear on him for the content I'm starting. I still can't understand how Fabian keeps debuffing him when I have his res at nearly 800 (without res leader buff). At times I still feel like 50:50 of the time, it doesn't matter which set I have him in.

I only swap for a couple cursed city stages each month. I could swap pve builds onto marius amd others but never have bothered. 

I do for some things. For example, I swap gear on Horsey for FW hard 21 from his usual arena set-up.

And I have several sin city presets i bounce around to whichever epics are eligible for that stage/rotation

I swap for a couple of toons for HFW and for a couple of stages in Sintranos every rotation, but the spot I use gear swapping the most is for Siege prep.  I do at least a couple of post restriction teams every Siege, and depending on which toons/teams I am using across all 4 of my Posts, I swap gear to make sure I have the best possible defenses up.

I know some peeps that will have dedicated PVE/PVP builds for certain toons (like Marius) that they swap back & forth, but I don't do that.

Only my Cursed City champs get swapped around.  

I should start doing that for siege, but just never get around to it

Worth it.  Gear presets honestly one of the most game changing things they ever did. 

I run a lot of restricted post teams. Sometimes all 4 of my Defense Scrolls.  Off the top of my head, I have Epics, Sacred Order, High Elves, Force, Knight Revenant & Nyresan that are all in our current rotation.  Used to have a few others as well.  They are all good as built but Swapping Gear makes them better....for example, if my Arbiter is not in use, that speed gear goes nicely on someone else....  

No rare team?  That one's the best. 

I have some solid rares leveled & mastered to build if I ever need to run that team in a pinch, but I have three clanmates with strong Rare Teams already built.  

Makes sense.