Andrew is spot on about Surrey, not a bad soap, and it's cheap! The one advantage over Williams is that the Surrey is not as dry as Williams, and is actually a bit easier to develop a good lather with. The disadvantage is it has a short life...you don't want to soak this in hot water before using or it will disappear very quickly!
I like to make my expensive products go a little farther and appreciate them, so once a week on average I use either Williams or Surrey Deluxe. To be honest, Williams just falls short and is a lot of work compared to a better cream or soap, but I can get as good a shave out of Surrey as I can most other products. It isn't as enjoyable, but boy does the good stuff seem so much more enjoyable the next day, though it is really only about ease of use and scent more than the quality of the shave.