As time goes by, the story of how Dom Perignon dedicated his life to removing bubbles from wine, will become more mainstream.  

Chistopher Merret's paper to The Royal Society in London, on how to create Fizz was delivered in 1662, some decades before our famous Monk got to work on elevating the perception of the 'still' wines of the Champagne region.  

All of this is becoming irrelevant since there is now no doubt in my mind, the Fizz produced either side of the Channel can be equally delicious. Pour yourselves a glass of each and decide which you prefer is a relevant concept with New World - Old World Chardonnay/Cabernet/Pinot etc. as much as it with anything Fizzy.

Time to put things to the test... You may discover that you really like both! Then it may come down to price...