Teach me all about NH crop cutter balers.

Ok I currently have a NH 648 SS baler with bale slice that is getting long in the tooth and is about time to make it the backup baler. Looking at some BR7070 and RB460 balers and there lot of crop cutters for sale it seems. How much power does it take to run the cutter in high moisture crops? Can the knives/cutter be removed to bale "normal" uncut hay? How is knife maintenance? Thanks

Teach me all about NH crop cutter balers.