The LucidSound LS30 are amazing, just got them on sale the other day for $99. A lil more than then you wanted to spend, but well worth the investment. They are universal so u can use it on your Xbox, ps4, comp, or even your phone. Super comfortable, look good, sound great, by far the best headset I have owned. So if your willing to spen a lil more, I would def recommend these.

any headset you want .. as long as you pay 20$ for the adapter

http://www.xbox.com/en-US/xbox-one/accessories/headsets/stereo-headset-adapter

New generation pads have aux but if you have old one, yep u need to buy audio adapter (or maybe if you like chatpad with aux :))

You don't need that.

All you need is a 2.5 to 3.5 stereo adapter. I bought this one, it's $6.50 and it works perfectly with my x42s.

https://www.amazon.com/gp/aw/d/B00MG73JV2/ref=pd_aw_sim_sbs_107_2?ie=UTF8&psc=1&refRID=SHDM3AZ31N32A07EK10K