35R, my first job out of college (2001) was Superior Aviation, flying Caravans. I had a blast. I have one question, did Martinaire keep the Metroliners when they bought Superior? If so, will you have access to upgrade in the Metro after a year or so? I went that route and it took me about 4 years to get into heavy 121.
If you go the caravan route, my advice is to get some right seat time in the metro after you fly the Caravan for a year, then get a job flying car parts in a Falcon or lear freighter for a couple years and in about 4 years from now, you'll have a really nice resume with 1000 pic in the Falcon or Lear and some great memories and excellent flying skills.
Good Luck!