It's not just for troubleshooting. AppleCare for all apple products are a great asset. iPhones, macs, etc receive great customer service.
SquareTrade FTW IMO, awesome customer service and never had a hassle with a claim.
The Samsung kiosk near my has always been pretty good with my Samsung products as well.
Apple has always been great as well, no complaints with them except the one time they tried to tell me my iPhone had water damage and wouldn't fix it, actually making me feel like I was wasting their time with my mistake. A talk with the manager and showing her the unactivated water mark changed that up very quick. I know Apple had a lawsuit they lost in relation to that water mark crap, they turned away a ton of innocent customers from what I understand.