This is basically Doctor Who Does A Western. They only stop off so that the Doctor can get a tooth extracted at the dentist, but a case of mistaken identity sees them all in trouble before long.
For the most part, Steven and Dodo enjoy their time in the wild west, occasionally pretending to be American, which is sadly how most of the period characters sound too. Some very dodgy accents going on here.
It wasn’t terrible, but by the end of the fourth episode I was getting pretty bored with it, even with the shootout at the OK Corral. There’s a sort of musical vibe throughout, with an ongoing song about their antics, but it’s overused and really starts getting annoying.