in the sense that it seems to strike an exact middle ground between good and bad. It's a fun, well-written, well-produced episode with extremely memorable imagery (I've distinctly recalled the visual of the Doctor jumping cars on the Motorway ever since I first saw it) but it's just kinda overstuffed and scattered?
It feels like it wants to make some commentary on drugs, while also making a satirical commentary on traffic (maybe?), while also cramming in a completely superfluous classic villain that doesn't even resemble the original in any way, while also also continuing the weird arc with the Doctor and the Face of Boe (if you can call that whole thing an arc... he appeared like 3 times, and the second time there was a "legend" that concludes here with him just vaguely teasing at the events of the series finale and then dying.)
It almost feels like it wants to be a two-parter, but there are already quite a few two-parters in the series so they tried to condense it down.
I feel like it could've been a really good episode if it had committed to any single concept, like the traffic thing. Imagine if Doctor Who made a commentary on car dependency in 2007. But maybe that was too advanced for the time 
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