A quick thought or two....
Keep in mind what kind of operation each of the carriers has;
NAS = low-cost, which can be very uplifting when you think about a/c orders and time to command. On the downside, they always go for the most profit, meaning existing bases can be shut down (as well as routes) if they are not profitable enough.
WF = shortfield regional operations flying argueably one of the worlds toughest route networks. This is not for everybody, but for those who like a challenge and have the flying skills required. Thus, time to command is a bit of a wait (approx 8 years I think). Regional carrier, and owned, by SAS, and through them a STAR Alliance member. Flies for the Norwegian government sponsored routes, mostly to keep the infrastructure alive

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Two totally different kinds of operations, so you can`t really compare them side by side. I think NAS works a 5/4 5/3 schedule, while WF works a 7/7 schedule with starting/ending days being the same unless you bid otherwise. In WF you`ll almost 100& be assigned to Tromsø or Bodø, and you bid your way Southwards if you like.
NAS = meet with a current 737 rating
WF = you get paid from day 1 during groundschool
Other benefits can be found on
www.ppjn.com but be advised that WF pilots have just been given new and improved benefits, especially nice for commuting pilots
Good luck on your choice. Keep us advised

And feel free to send me a PM if you have any Qs