The biggest issue for express is that they can't control when people show up to the houses. So even if you use express you have to be mindful of the crowd flow to the express people. Since they don't care about lines the average person will work front to back in sequence. Also what ducks for express is that they seem to keep the ratio for merge consistent regardless of express length. Only time I have seen them really favor express was at tent 2 a few years ago when express line back up into the park.