You are correct Seat62K - the US is one of the few countries where you can't get an Electron Card
Visa Electron - Wikipedia, the free encyclopedia
It's not all that frequent in the UK mind - there's only 3 or 4 banks that offer the card.
Final3Greens - don't worry, I spotted your sarcasm. I was thinking of the £16 one way cost for Heathrow Express compared with the more respectable £6 odd Connect single, or of course, the much cheaper Tube fare...
But back to the topic in hand - do your research, and if you do decide to go for Ryanair, make sure you don't fall into the trap of inadvertently buying their travel insurance...