Doesn't Bowden throw pretty hard as well? Papelbon/Lester hard vs. Beckett/Bard hard?
In either case, from everything I've heard Bowden has tremendous complimentary stuff as well, and Bard is a chucker so far. Let's hope they all develop into hall of famers and the sox have a Beckett, Papelbon, Lester, Bowden, Bard rotation in a few years.