I have flow both pax and cargo 135 single pilot. The good thing about having pax is that you need an autopilot. I used to fly 135 cargo Be1900, and this job was fun but no autopilot. If you are confident in your skills and your airplane you will do fine. Just remember at 0300 going into uncontrolled fields with bad WX its all about using your check lists and taking you time to do everything right. One of the most dangerous parts about small 135 ops is not your hide but your certificates. Do not do anything against FAR's, I have known pilots that got violations at their 135 jobs and that has slowed and even stopped the career. One of the places that I flew for we had SIC's in the C-208 this was more of a babysitting job. But thats how I started building time so more power to them. Single Pilot Ops are only as safe as the PIC wants to be. Dont be afraid to say "No way" if you know its wrong or dangerous. Those jobs are fun and make you a good pilot. Any way thats my 2 cents