Ethanol has always been in gas, there is more now and I am sure it causes some problems, rarely, like everything else.
Ethanol has become the buzz word/scapegoat for every problem that develops in boats and I am sure it is not.
If you have things that make you more prone to problems like a Fiberglass tank then you are at risk. If you don't, you will probably go for years and never know what kind of gas you have.
All gas will give you problems if you let it sit too long.
Cheers,
Pismo
1996 22 Classic
Red with Stainless Windshield
Stock Gen VI 502 Magnum MPI-415hp
Stock Bravo I
25" Mirage Plus
74.5mph best @ 5050rpm GPS (Speedo said 80)
27" Labbed Mirage Plus
75.5mph best @ 4800rpm GPS (Speedo said 82)