Is this worthy of a replacement?

[Ni.Hao]

I've had an iPhone 5 for a few months, and the lock button has suddenly began to act sporadically. It works (usually) on the left side, never on the right side, and usually never in the middle. It still works, though, so I wouldn't want to pay to have it replaced at this point. The nearest Apple store is an hour away, so I'd like any opinions from someone else before I make the drive!

 

[TyPod]

I'd say it's worth a try. If it looks like it's a problem when you show someone at the Apple Store, they should replace it for you.

 

[mactumors]

My WiFi stopped working in the first month. I called AppleCare and they overnighted me a new one and waived the $30 charge. My Apple Store isn't close either.

You're still in the 90 days of phone support. Call and tell them what's happening.

 

[dictoresno]

I've had an iPhone 5 for a few months, and the lock button has suddenly began to act sporadically. It works (usually) on the left side, never on the right side, and usually never in the middle. It still works, though, so I wouldn't want to pay to have it replaced at this point. The nearest Apple store is an hour away, so I'd like any opinions from someone else before I make the drive!

https://forums.macrumors.com/threads/1550615/
https://forums.macrumors.com/threads/1550414/
https://forums.macrumors.com/threads/1472631/
https://forums.macrumors.com/threads/1542734/

been discussed PLENTY of times. they will replace it under warranty.