I just did the Momentum Mogul winter clinic this past weekend at Whistler. It was two days of instruction from former WC/olympic mogul skiers. If you can ski with separation, I think it is a great investment. There were a couple of students in the groups that skied square to their skis and struggled considerably more in the bumps. You really need to have upper/lower separation to ski the direct mogul line that the clinic aspires toward. There were some drills in the morning to work on short turns/separation on groomers. The coaches took all of us into the bumps in the afternoons when they had turned to slush, whether everyone had mastered separation or not. Those without separation had a much rougher afternoon than the others. Still, it is useful to be in the bumps to learn how to read them and work on absorption even without good separation.
It was pretty interesting watching the coaches ski. As luck had it, there were a few Whistler Ski school high level instructors teaching in bumps as well (advanced lessons, not part of the clinic). I watched the Momentum coach ski down the same mogul field just after a ski school instructor. The two styles were very different. The Momentum instructor's head went straight down the fall line. Barely moved one helmet diameter side to side. The Whistler instructor had a much rounder, longer turn shape and was comparatively all over the place on the same run. I wish I had taken a video of it. Both guys moved quickly down the bump field, but the Momentum coach showed a whole other level of mastery. Pretty eye opening to see how much less jarring the direct line was to the body when applied correctly. Crossing trough lines in the moguls like the Whistler ski school instructor did suddenly looked much less efficient.
Momentum coaches are not required to have any teaching certification with CSIA or PSIA. So they had totally different drills and ways of looking at moguls than I had heard before. Whereas former lessons I have had with PSIA and CSIA really preach versatility and teach to that, Momentum is very singularly focused on one thing - skiing a direct line in moguls.
The Momentum class I was in had student ages ranging from late 20s to mid 50s. They also get kids taking these clinics, but they are taught separately from adults. Group size was 5 students to one instructor. They did video analysis after lessons each day. My coach on day 1 was Ryan Johnson (age ~45) and day 2 was John Smart (age ~54). Both are former Olympians (mogul skiers). Pretty cool to ski with these guys!
If you ski mostly square to your skis, I think you will get a lot out of B4B or Clendenin method lessons. If you can ski short turns with upper/lower body separation and want to learn bumps, I highly recommend the Momentum Mogul clinics. You can also arrange for private multi day lessons with their coaches. If I had unlimited time/money, and wanted to get really good at bumps, I would 100% book a private lesson with one of the Momentum Mogul coaches for multiple days and just follow them all day in the bumps.
They also have week long clinics/camps in the summer. Website for winter sessions:
https://www.momentumskicamps.com/programs/winter-clinics/