I bought normal apple care (which was all there was then) after I had a malfunctioning port on my new iPad. FIgured if I got one with a bad port, stood a chance to get a second one. Never collected on it because I never needed to. Now my iPad is over 3 years old and has no value beyond me using it (and my niece playing her games)
A rule of thumb about the warranties, how you use your device, what they cover, and the replacement cost. Office Depot wants to sell me a replacement warranty on a thumb drive I got for 29 dollars....no. because chances are if the device malfunctions the replacement will be affordable enough to have going through the warranty to be more trouble than it's worth.
I did however get the 'step on it and we fix it' warranty with two laptops I had. The first time it paid off because they were going through a batch of bad motherboards and mine was replaced 3 times, the second time when I had an issue I got to work through the scripts of a very polite man in New Delhi who insisted my issues had to be software.
My last laptop I bought it because it was like $60 for 3 years of accidental damage, which was cheap enough to gamble on. I think the 3 years of coverage on the tablet I got for Christmas was $60 or so, and it's 3 years of accidental damage.
But you also need to look at the cost of the warranty + service fees and compare them to the cost of replacement. How much is Apple Care plus? (regular apple care used to be $99), then if you have a $79 service fee, well you're at 178 dollars. An out of warranty replacement runs from 219 to 299 so, basically, can you absorb that 40-120 dollars if your iPad is damaged? If so, then keep the money. If you can't absorb the cost, then you may be better off with the coverage.
Same premise as car insurance and the deductible. If you can absorb a $1000 deductible, then save money on insurance by going for a cheaper plan with the higher deductible. if you can't, then you may be money ahead to pay more monthly to pay less if you need it.