After you have taken a load of blank flash shots, because the lens synch for flash is at the wrong speed, I think you will appreciate why it's stuck down I would advise you to ensure you do the same with all your lenses,this recommendation comes as you can imagine from experiences too painful to recount. I have used Mamiya C330F gear for about twenty years, and once you've bought a truss to carry the outfit, and if you're not too knackered when you get to the the location by the weight, it's a excellent professional quality system capable of impressive photo-technical quality that after all this time sometimes still astounds me. Try shooting the same filmstock with your 35mm camera and your Mamiya, and compare the results.
I hope you get as much pleasure from it as I have mine
Best wishes Bentley.