Still amazed that we allow the regulators to drive requirements to the point where we would rather over-regulate than provide the resources to save lives. Class D hoist is "a hoist for hire." If you are putting folks from a perfectly good aircraft onto ships, power lines, or windmills as part of a job, you are a hoist for hire. That's class D. You are on a daily basis putting lives on the hoist.
HEMS demand for hoist is typically more situational. It gets used less often, the attach points don't get stressed as often and it doesn't warrant the level of overdesign demanded by the class D requirements. I mean, less face it, places that don't require class D for SAR are not plagued by hoists falling off aircraft... but some bureaucrat sees that HEMS helicopter crews occassionally get paid and so they consider it "hoist for hire" and drive up the cost. I'm sure someone thinks they improved safety by imposing a higher level of equipment requirement, but when it robs the public of adequate resources to protect the public, it's no service.
I'm waiting for them to determine that ladders are too dangerous for saving people from fires. Either the fire company gets a cherry-picker or we let folks burn. Same thing.