Originally Posted by
barba
Don't forget the weight of the $20 bill if you go with the Ultegra. I would take the 105.
On the face of it, 105 seems like a good deal. However, I've found that the slightly different design of the ultegra cassettes wears the freehub splines to a lesser extent than 105, which has a tendency to chew some pretty sizeable notches in the splines.
I use ultegra cassettes on my bikes, as it seems to be the best compromise of design/quality and cost.