Rear facing drop outs or track ends are the best. I love them. So simple and easy to tension the chain. And together with some chain tugs it's a bombproof set up. I never had any problems with mine...Eccentric bottom brackets are just a problem waiting to happen, those bolts will eventually strip or become seized, No thank you !!..I have no experience with sliding drop outs, but I just don't trust them...I just love the simplicity and reliability of track ends or horizontal drop outs.