I have a 2023 C8 and have been filling 94 Octane gas at Petro Canada so far. Upon further researching I have learnt that almost all gas in Ontario now has Ethanol. I called Shell and they said that their Nitro V-Power 93 Octane has only 5% Ethanol. Planning to switch to Shell as they are Top tier rated and that is recommended in the manual . What are others using and is there a recommendation on what to use before putting it away for winter? Any opinions on Costco Gas which is also rated as TopTier. Appreciate the insight.