Damn Crab, you really are trolling for bites with that one.
I haven't done SAR, but have done HEMS where the criteria you list are met. Have also worked in the single pilot charter environment. There is simply no comparison as far as workload goes, either on or off the job. The lack of team (crew) on the job, and the lack of team (back office support) in the SP corporate world means the workload is simply immense.
TT