In my opinion, one is not better than the other. Lalvin might be a little easier to find, but as far as making the cider hard both of those yeasts are great choices. Try them both and just chose the one you liked better.
I would definitely choose the Lalvin 71B. This yeast is easy to find rather Red Star. Heck I could look it up in e-bay, and there it is. To me, it is necessary that I get my ingredients as soon as possible so it may not take long for me to decide which brand I should choose. Both a good in quality. They do the same action.