The Monkey and the Grom have manual clutches, the CT and the Supercub are auto clutches. Personally I prefer the auto clutches, makes them feel like the old C90’s, but that’s just the nostalgia kicking in. If you avoid big roads the 125 engine is great, pulls strongly, and the four speed box makes all the difference. Having said that it will maintain 55mph comfortably so big roads aren’t that bad, it’s just that you don’t have much in reserve. £5k is not outrageous for a CT, look at the price of any Jap 125, and then consider they have to do a fair bit to have them shipped over, and pay duties etc.
If you are budget conscious a used Supercub is half the price, and almost as much fun, just not got the off road vibe going on.