I have never had to use Epson's warranty. I did have on going problems with one printer a few years ago and Epson helped me even though the printer had recently gone past the warranty period. I think this says something about Epson's overall commitment to their customers.
I think you should be fine with any of the vendors you mention in your post. I have purchased from Adorama, B&H, and Amazon and they are customer conscious and respected sellers. I have limited experience with the Epson Store but they have also been very good at customer service and overall responsiveness. I am not all that familiar with Epson's policies on their extended warranties and I would recommend that you contact both the vendor and Epson to get information on purchasing additional manufacturer coverage.
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