I have used E 10 almost exclusively since 1995. We have always trailered our boats and fuel up at a local gas station. Our previous 190 Horizon had a Volvo (Ford) 5.0 EFI that required 89 octane. Our current 268 Vista has the GM 5.7 Gi that requires 87 octane. In Minnesota gas is E10 by state mandate. The only other choice is the occasional gas station that offers 92 octane without any ethanol for higher performance engines and some old legacy engines. We put over 2000 hours on the 190 and over 400 hours on the 268 without any engine issues. There are factors to consider. Make sure you are getting fresh fuel and use a fuel stabilizer if the boat will not be used very often or over winter. Try to avoid fuel contamination or water. Change filters / water separators on a regular schedule. Get out and use your boat

Go have fun with it.
Different parts of the country, or world, have different views on ethanol. I am not here to debate the issue. I will say that my observations include:
1. In some cars I have noticed a small reduction in fuel economy, in some cases as much as 10 to 15 percent between E10 and E85. Little if any change between E10 and non-ethanol fuel. Higher octane fuel than what your engine requires is usually a waste of money.
2. I have not had issues with water freezing in gas lines in cold weather since using the E10 gas. E10 will absorb some water and run it through the engine without noticing it.
3. Some say they have noticed a difference between E10 and Regular gas without ethanol. Its my understanding that most relatively modern engines are made to run on E10.
4. E10 contains more oxygen molecules than non-ethanol fuel. This causes a slightly leaner fuel mixture and possibly a hotter operating temp.
5. E10 is reputed to be a cleaner burning (reduced emissions) fuel than non-ethanol fuel.
6. Many marinas sell a higher octane ( 89 to 92 octane) non-ethanol fuel as a "one choice fits all" situations.
In the end, if you prefer to use non-ethanol fuel you will probably be able to find it. It may be more expensive than other options, or maybe the only option. Any choice, fuel or anything else, has its pros and cons. Be aware of the benefits and limitations, and adjust as appropriate. Hope this helps.