I have been on several log flume rides from one Six Flags park to the next as well as one of the best in the business at Universal Islands of Adventure. Overall, the Log Flume at Six Flags St. Louis does not disappoint, but it does not give anything unique to the "log flume" ride experience.
One nice feature about the Log Flume at Six Flags St. Louis is the fact that there are two completely different tracks, so your ride experience can differ depending on the side. Additionally, the ride typically operates the photo spot on its busier days, so it is a good ride to capture a memory because the entire family can fit into the log for the picture.