RE: CA 34% Extra
I think that Carden makes the best looking and most durable wood plane out there. However compared to the CA it requires much more building skill, takes longer to build and cost more. The CA is fairly easy to build, and while the instructions do leave a lot to be desired, they are also not really needed. I too have thought about the same choice as you and decided to go with the CA as I am not a great builder. The CA is a high quality kit and I have no regrets.
If you love to build and you are good at it, buy a Carden. If you want a high quality, fast building kit at a great value, get the CA.
FWIW