Has anyone found that the City Passes are helpful? I'm debating whether I should purchase The London Pass/Paris Pass. Your help is greatly appreciated!
In cities where every museum costs money, I like the pass as a way to "allow" myself to make short stops at minor museums.
If I don't get a city pass, I'll skip a museum that isn't on my must see list, or wouldn't spend a long time at, rather than pay the entry fee.
London is hard to recommend because so much is free (you may not have enough time to visit all the free stuff). Other places a pass works really well, especially if it includes public transportation.
IMO, both the London Pass and the Paris Pass are a waste of money.
In London most major museums are free and you can save on transportation costs by buying either a travelcard or an Oyster card on your own. For more information, visit the official Transport for London site and/or the London Toolkit site.
In Paris you'll do better buying the Paris Museum pass on your own so you aren't stuck with the overpriced Paris Visite transportation pass that comes with the Paris Pass. For a list of all your transportation ticket and pass choices with links to detailed explanations of each one, go here.