Did the 747SP have dedicated flight crew, or were they part of the 747-200/300 crews?
I was never lucky enough to fly one*, but I know a few people that did and they reported them as being quite similar to the regular versions. They have a common type rating with the regular Classic as well.
* I did get asked by Luke Butler to take his from Brisbane to Asia, but I declined. Three of my other mates did the job.