I vote for the CAP 10
I started my ppl in the c150, and after about 10 hours total, and spending an hour or so doing solo circuits in it, decided that i didnt really want to spend £££ on flying an air bourne 2CV. So i decided to change AC, I had a look through the fleet, and the PA28 didnt appeal, but i quite liked the robin, after doing my first trial flight in it, however, I really liked the look of the cap. It looked IMHO, what aeroplanes should look like, with the wheel at the back, and a big (compared to the c150) engine at the front, however, genaral bar banter told me i was daft for wanting to learn in it.
I asked an instrucor if I could learn in it, and there was a general negative murmuring, and that I should learn in a PA28 or c150 like everyone else, but i persisted, and eventually, the CFI told me that, although no one had asked to do that before, that there wasnt a problem with it, the only problem for me would be that i would have to spend more time in the circuit before i could solo, and that it was a bit more expensive.
I completed my ppl in the cap in april, and Im very pleased I went against the general advice that it would be really hard, and went along with what i wanted to do.
It had a lot of atributes of a good teaching aeroplane, it is not difficult to fly well, but does get upset if you use the rudder pedals as footrests, ignore crosswinds, or try to land at the wrong speed. It is also cleared for spinning, has excellent all round visibility, and you can add the odd loop and roll onto the end of boring lessons like slow flight
NB