It felt like I was watching The Twilight Zone with the oversized props throughout episode one. This added an extra element of fun, slightly different from the rest of the show around it, which is usually a good sign. I would say though that the 'giant world' novelty does wear off during the second part, somewhat saved by the more engaging storyline.

The Doctor feels more in charge at the start of this season which changes the group dynamic, he feels more like the character we see in later seasons. The sets are the best in the show so far, it feels like they had higher budget to play with (though another tardis.guide user suggests that these are re-used sets from another show - makes sense!)

I liked the idea of the Doctor and his companions were fighting an enemy that did not know they existed, in such a surreal episode a welcome element of realism in the baddies' ultimate plan - to sell unsafe products to the market!