It doesn't matter what you fly, it matters which offers more stability in terms of trying to make a career out of this mess. If you feel that the Turboprop job offers more stability, then do it. If the jet job offers more stability, then do that. I flew the 747 and there was no job security where I was working. Not having peace of mind was a complete nightmare. I haven't been able to work/fly for 21 months.
Morale of the story: Find a company that offers a somewhat secure job (tough to locate, but some are better than others). I'm assuming you have some seniority where you are. Don't flush that down the toilet in pursuit of a shiny jet. The ironic thing is that the turboprop is probably more difficult to fly than the jet. (less levers on the jet and handles much better during engine out procedures). There is nothing difficult about transitioning to the jet. The only difficult thing is the stupid mindset that exists concerning TP to jet transition.