to get their bonuses?

or are those permanent, from the point where, you've picked them up?

I'd like them to store somewhere, so that it becomes easier to find other letters in the 'Misc' section

You don't have keep them. Once you've read them, you've got the boost. I sell mine as they're generally worth a few caps.

I haven't tried storing them on a built magazine rack yet - be a shame if we can't, tho.

I just put mine on a rack I built in one of my settlements to see if they stay there or get swiped by npc's. Yes, you keep the bonuses.

OMG DONT SELL IT, is the best collective Bethesda have made, make a Magazine shelve and u can display it there and see all the different ones.

I'm making the assumption that having the magazine rack (and the Bobble-head Display rack) adds to the Happiness factor for my residents. I assume they count as decorations, and from what I understand, decorations help to bump Happiness. That's assuming, of course, that the basics have been taken care of.

Even if that's not the case, they make ME happy, so I keep them on display.

Fair enough. Hopefully NPC's won't gank any of that stuff. That's what I'm trying to find out with my magazine rack experiment.

i have my personal collection on my home on Diamond city. I didnt know about the decoration factor on settlements.

2nd best.

The multiple complete volumes you could collect in Skyrim and then display in your personal library was better

I'm keeping mine on a magazine rack in my Sanctuary Hills home. No-one seems to have stolen any yet, if they do I'll either have to take the stairs out so they can't get up to my floor, or shoot them in the face.