Is this earring good for sensitive ears?

It is made of 316L stainless steel, which is a low-nickel material many people with sensitive ears tolerate well. It is not certified nickel-free, so check with your piercer if you have a known nickel allergy.

Yes. The flat back sits flush against the skin, so it does not poke when you lie on your side. Many buyers leave it in for days at a time.

What size post does it have?

The post is 8mm long and 0.8mm thick, which is 20 gauge. That gauge fits most healed lobe piercings.

How does it compare with butterfly-back studs?

The screw-on flat back holds more securely and is more comfortable against the skin. The trade-off is that it takes longer to put on and take off than a butterfly back.

Is it a good first pair after a piercing?

It is aimed at that use, since the thin 20 gauge post suits a healed lobe. Wait until the piercing is fully healed and check the length with your piercer.