Originally Posted by i killed judas.
would i be able to use a 10 speed shimano cassette with everything else shimano ultegra (brifters,FD, RD)?
Absolutely. In fact, 105 cassettes are a pretty good deal. They're all the same in terms of the tooth profile, etc., but the Ultegra and DA cassettes are lighter and more expensive. So if you don't mind the extra weight, you can save a lot of money by getting the 105.