Robert_Charlton - 8:49 am on Feb 26, 2010 (gmt 0)
I always use the 100 results per page option; I turn it on in every computer I put my hands on.
Those who use this option for rank checking should keep in mind how Google clusters. If you have, say, a #1 result and a #100 result for a query, with 100 results per page Google will cluster them as #1 and #2, which might give you a false sense of confidence. ;)