If you swap loadouts when not in the main screen(companion and gear screen) you get a lag spike. Seems like a loading issue because it only happens the first time you swap between 2 loadouts per time you open the arsenal after that I assume it is cached so there is no lag spike. Eg. open the arsenal and go to the gear or companion screen swap loadout from A to B get lag spike does not happen in the main screen. After that, swapping between A and B does not cause a lag spike but if you close the arsenal or swap to another loadout lets say C it will cause a lag spike.
Duplicating a loadout causes it to duplicate multiple times. Not sure what causes this but it is a problem might be changing items immediately after duplicating because I will get a exact copy of my loadout as if I didnt change anything after duplicating and another one with my changes not sure if this is true every time because I havent been paying too much attention but this has happened every time so I noticed. Sometimes this causes no companion to be equipped or something random gear being equipped not sure if there is a pattern. Eg. Duplicate loadout, change item(cause that's what I usually duplicate a loadout for) and reload(enter dojo, relay, mission etc) see 2 loadouts with the same name. Can go over loadout limit.