One advantage for the new instructor (FAA CFI) is that all the information is still fresh and he keeps repeating it for a 1000 hours and that might be an advantage.
Flying wise I think having a more experienced instructor is just better, there are a lot with 200 hours or less, who can't really fly. The perfect mix is instructors with commercial 'real life' experience. But again this is my opinion.
Are there that many accidents with low-time instructors? Answer yes, read the NTSB reports.
As you already know I'm not in favour in this discussion of JAA or FAA.