So here's my story: I've never dropped a phone myself or gotten insurance for it, but have generally used Square Trade for phones of my less coordinated family members, and have been generally happy with Square Trade.
Planning to use my S6 naked, I decided to get Square Trade insurance for myself this time as well. About 2 weeks into having my S6, I cracked the screen. I didn't drop it mind you, but inadvertently put it into the same pocket as my car key while I went for a run. The one spot where the key was rubbing on the screen resulted in spider cracks running in several different directions.
Anyway, Square Trade was very good, but my only option for repair was to go through Samsung directly since they are currently the only ones with the necessary parts. BTW - the total repair job at Samsung for a cracked screen will run you $237 after shipping and tax, which Samsung also charges.
So for me, the insurance has already paid for itself. I understand those that are of the opinion that phone insurance is a bad deal. While I generally agree with that, it really depends on your use case. In my case, for example, my family ensures I never lose money on the insurance. :'(
I don't know if I'll continue to get insurance on my own phones in the future because I consider this one incident to be a fluke, but in this case I do wish I would have gone with Samsung insurance given that the pricing is comparable to that of Square Trade, and it would have made the whole process easier to just deal with Samsung alone.
That said, if you're indifferent to dealing with one or two companies, then I would recommend Square Trade based on having several successful claims processed through them over the years, including one for my S6.
Hope this helps those considering the issue.