Napoleons uses CIC chips even if the place is a dump, and the Palm Beach is probably the nicest casino which doesn't charge a membership fee (is just off Berkeley Square, about 20 minutes walk from the others mentioned and about 400 yards from the Ritz). The Vic probably has the largest selection of chips if you want to pick up different varieties, although the Palm Beach does have 10 different inlays on their £5 chips!

Jason