I’ll buck the trend by saying that some MSA’s have improved slightly over the last couple of years or so. Showers tend to have been modernised, or in some cases like Pont Abraham and Sarn Park added for the first time; I can’t remember the last time I couldn’t get a shower because it was out of order.
They’re still ridiculously expensive for what you get though. In the owners’ defence, the ■■■■ smell isn’t their fault at all but down to the dirty lazy drivers who can’t be bothered to either use a bottle then empty it down a drain in the morning, or walk to the main building or garage. And before anyone else pipes up, the vast majority of culprits seem to me to be British drivers.