[austin420]

so lets start with what the insurance is. for the 8 dollars, you are paying 4 bucks for "esrp" and 4 bucks for "erp".
esrp= equipment service and repair program aka sprint service center
erp= equipment replacement program aka asurion

although you are covered for 1 year under manufacturer warranty, that warranty is serviceable by sprint. they will typically fix most things for you that they deem not physical damage. they dont have to do this. it is in their power to make you claim warranty via htc, samsung, whoever. they usually dont do this though, as they wnat your business.
after the 1 year is up, they usually wont service your phone, but try to sell you on an upgrade.
esrp gaurantees that they will service your phone in store for the lifetime of the phone that you are paying it. also, if they cant fix it, they will give you a new one, usually same day. with just the manufacturer warranty, they will make you send it in to the phone maker. that can be a 3 to 6 week wait, and your at the mercy of a off site tech, that may or may not deem your phone unrepairable.
the esrp is a life saver, as you can usually use it to replace bricked phones, and things you may have caused using sites like ppcgeeks.
erp, aka asurion does have an addional 100 dollar deductible. the only time you should have to use this is if your device is lost, stolen, water damaged, or physically broken as in cracked screen or smashed in to pieces.
i also think this is valuable as they run out of stock a lot and have to give you a comparable model.
i used this loophole to go from touch vogue to touch pro to touch pro 2 using no upgrade. they just offer you the next model up.
more recently i had to file a lost device claim on an epic 4g (the old one) and got an evo3d. its a good way to get a new phone with out extending your contract or using your upgrade.
personally, i find that it is worth keeping until the phone can be found on ebay or craigslist for under 100 dollars, and by then, ive usually gotten a newer model anyway.