Runes of Magic US / AU

Wings are basically an extra piece of gear to attach stats to. They can also be plussed to give a bonus to XP TP and drop rate, if I'm not mistaken.

I don't believe it matters which ones you get.

It really does not matter what wings you will get, except it would be nice to get some OD ones, but those are rare as far as I know.

People mostly stat those, and then hide them.

Yes, all wings are the same, except for appearance. Some promo wings (Sismond's) weren't giving XP/TP/Loot bonuses, but that got fixed 3-4 months ago. As far as I know, those were the only bugged ones, and now all wings are identically enhanced when plussed.

Wings are the only item that does nor drop from mobs and only comes from item shop. That is why all wings are 100 dura. The only exception was the event run once or twice a year that involved spawning instance bosses in world. They could drop wings and as any boss drop, it could be OD. Chances of getting that... slim and none. They are rarer than hen's teeth; or, as Atar would likely say "rarer than good sales ideas from sales department". :p

Stones you can get from NPC in Varenas will not get you far. CS stones on other hand work much better, but cost money.

Wings have hidden (ghost) stats, and they give bonus XP/TP adn drop rate.

Drills create slots for runes on wings, and just like any other piece of gear in game, you can add up to 4 slots for 4 different runes. (have to be careful as some runes are only for weapons)

Here is RuneDB link for Little Devil's Wings. Take a look at refinement section, for each plus you get bonus %. At +12 it's 20% and if hammered (which they should be if you state them), then it's 24%. It might not seem a lot, but if you think that on every 1M xp you could get additional 200K (and more TP as well), then yes, it makes sense to plus them.

Hope this helps.