Absolutely right Eddie - I can't believe valve master and the like is still being sold! It's completely redundant. As far as ethanol goes, as pointed out apart from its' effects on fibreglass tanks and some tank sealants it doesn't seem to do anything apart from improving performance, at the expense of fuel consumption. That has been my experience here in Australia, but who knows how the brews we get compare to other parts of the world. In countries like the USA, where ethanol in fuel is mandated, there must be ways of avoiding issues with ethanol in older vehicles - ethanol proof tank sealers for example. In Brazil fuels have 85% ethanol, so they would know how to avoid problems for sure!