While our DS was in flounder on our last
DCL Cruise, he enjoyed the club on
RCCL's Explorer when he was 3. Though he was hesitant at first, I found the cousellors very friendly and patient, none seem to not be happy with their job.
Our tablemates had kids 5 and 7 who had a blast in the clubs. We asked them if they considered a
Disney cruise, and they had ... a 7 night western RCCL was less money than a 4 night DCL cruise. That was the deciding factor. Without prior experience regarding cruises it was an easy decision.
We truly had a wonderful time and would to again. Being a DVC member makes the DCL cruise an bit easier (already had RCCL booked when joining DVC).
I believe your friends will come off the RCCL trip with a wonderful family experience. If it RCCL or nothing, of course, take RCCL and don't consider yourself short-changed by any means! Cruising is a great way to travel and they can't go wrong with either decision.