I'm at NetJets for almost 20 years. If you want to get to a major, stay 121. I upgraded to Captain in under a year in 2001. That upgrade will now be about 10 years. I expect the upgrade at a regional will be quicker. The flying at NetJets is definitely more challenging than any 121. But the majors will value 121 flying more. Getting to the left seat is key... and it ain't gonna happen soon at NetJets.