The bully is an excellent clutch, however, if you have to get it rebuilt, you may be better off spending a few extra bucks and getting the goldielocks from dover, they are a very nice clutch and are basically an exact replica of the bully, they look identical to a bully from what i could tell. I had the chance to look at the goldielocks in person this past weekend at the racers swap meet in Liberty ky, and i wish i had the money to buy the goldielocks, if i had the money i would have bought one. From what i have heard, they perform just as good as a bully and for less money spent. I dont follow the crowd when everyone says you have to have a bully if you want to be competitive, i run a Horstman X5 clutch and i was able to make the top 5 in a few classes at the Bluegrass Nationals and Turkey Buzzard races this past month.
I would go with whatever you have the money for, not with what everyone else says you should do. Either way, either of the clutch choices you mentioned are great choices in my opinion, alot of people use both and have great results with them.