I really hate random rolling this stuff. If something is worth doing, it’s worth doing with your eyes open. The link is awesome though for the analysis!
It's how a 1st lv character was allowed into the game possessing a Horn of Valhalla - that's not keyed to him!
Where do people stand on protective items? The rings and cloaks of protection, Magic armour etc. these are good for everyone.
My low level group got a one time use Horn of Valhalla because I had given them a "horn that seems magical" but nobody could identify it and then they forgot about it for 4-8 months at which point I had no memory of what I had been planning for it to be. It may well have been some sort of animal horn, or maybe I said "corn" who knows. We were just going by what someone wrote on their character sheet. So I went scrambling for something out of the DMG. I made it a lower level item by having it crumble after the single use rather than recharge after 7 days and having the spirits fade after the single encounter rather than an hour.
Pulling it out months later they still did another mediocre job on the arcana check so all I told them is that "it has some influence over the undead". They were in a fight with a room full of an overwhelming number of zombies and ghouls and blew the horn hoping it would calm them or something only to instead have five spiritual berserkers appear to plow right through their enemies. It was really perfect in as much as that was a large and dangerous encounter but not a particularly important or interesting one or one the DM had slaved over balancing in any way, so if a bunch of comical pseudo-vikings want to come and make a mockery of it then all the better.
Bag of Holding at low levels is great for most parties IMO.
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Immovable Rods can also be handy.
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Most gear dropped by mooks won't be worth selling due to the quality not being great IME. Also, the 500 lbs limit can be reached very quickly as well.These two might be far to powerful, especially the second one. The bag can be used to collect every piece of gear (and sell it of) that mobs leave behind, but the rod allows for evil shenanigans if you know how to do it.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.