Mate, I'm 52 years old. I've been doing this since I was 16, I'm properly qualified and have experience in a wide variety of the many aspects of this trade. I have never had one of my CU installations catch fire.
Now are you seriously telling me that because I am not CPS registered I am somehow incompetent?
CUs catch fire for one reason and one reason only. Poor termination of cables.
Now who is more likely to terminate a cable poorly, someone who was stacking shelves in Tesco a few weeks back and has passed some silly open book exam? Or me, an apprenticeship trained, properly qualified electrician with over 30 years of experience under his belt?