Many people argue over cycling with fish and I won't start that up. But I don't think you can say that adding a few fish cycles a tank faster then a fishless cycle. The low bioload of a few live fish will not establish bacteria nearly as fast as keeping you're ammonia at 5. With a fishless cycle you have to do water changes keeping the ammonia level low enough for the fish to survive that it slows the cycle. Even though some fish can survive a cycle it is also known that they due suffer from it and it will shorten their life span.