Which 9 speed Shimano Cassette should I get? I have a 40 minute (each way) daily commute that is particularly hilly.  I would like to upgrade the groupset of my faithful steel road bike to make my commute more enjoyable.  Money is precious at the moment so I have sourced sourced a Shimano Ultegra 6500 groupset, minus the cranks and cassette.  My questions are as follows:


Will a set of 8 speed Shimano 105 cranks (which I already own) work with the Ultegra 6500 group?
What new cassette should I buy to help me with the particularly hilly terrain I will encounter. 


Any help would be much appreciated. 

Cheers
Nathan
You can use a crankset thats market for 8 speed with a 9 speed group. Im assuming the 8 speed 105 cranks are already on the bike so thats one job done.
Personal preference. Hilly means different things to different people. Note the derailleur will provide some constraints due to its chain capacity and maximum cog size. But for hills, you want lower gearing (larger cogs). 


Go to your local bike shop and see what they sell the most for commuters in the area.