I went to a concert there two years ago; I am posting this from the parking lot.
It's a fine venue and the train access is a nice benefit, but the traffic pattern and parking are a nightmare.
The best advice is to park at the Stratford train station and take the train for one stop, during which they don't even have time to check for tickets. If we have to drive there, we now park at shopping center on the other side of the overpass. It's a longer walk, but it saves you the madness of the circuitous route to get out of the parking area and back on the highway.