Look people,... around here we've had 10% ethanol since the early '80s. Every tank, every time. I've never had a fuel pump go bad, or any fuel issue, and judging by what I hear from people around here this isn't a major problem. What we really need is to separate hype from fact... do you have first hand knowledge of issues, or are you repeating things you read on the internet?
I think we should do away with ethanol in fuel, simply because we need to subsidize it simply to make it affordable, and it takes from agriculture. But as a fuel itself there is no problem with it.
I used to live in a place (Brazil) where you could fill up with 100% alcool (ethanol). It's fine.
As for 15%... let me try to educate you on what your manual may say... in the corporate world, there are teams of people, several of them lawyers, who pour over every word in your car's user's manual. Every word. And they will seek to protect themselves (the company) against anything they can get away with. So if the standard out there is currently 10% at the time of writing the manual, the lawyers will demand that wording to that effect is written into the manual....... to protect the company! Not because someone from engineering came down and demanded it. The bottom line is, if the fuel system can handle 10% ethanol, the realist in me says it can handle 15%. It's not like the fuel pump is suddenly going to explode.
But... of course, since that wording is in the manual, if you have a car that is currently under warranty and the manual says 10%, you would need to stick with 10% to preserve your warranty. (Although I doubt they would even be able to prove otherwise, anyway.)