Yes i had problems with my block Ge Sleeving. Since i got it back i have had no problems. i have used ERL. Thats who SFP uses. They do Darton sleeves. They are also more expensive. I would say for the money GE is good. If you dont mind spending more ERL is a good route. I will say Chavez motorsports stood behind their block. There is definately something to be said about that. When i had a problem Kris and Kieth took care of me. I like doing buisness face to face if possible. GE is the least expensive, You have a local dealer(chavez motorsports) i would vouch for them anyday. So customer service isnt an issue because you would deal with Chavez not GE. Everytime i called Chavez motorsports i got a call back imediately and they did what they said they would do. You cant ask for much more then that.