I enjoyed my time at XO but don’t think you can go wrong with either choice. NJA is more of a career spot and most informed guys at XO will tell you that. Better Schedule, Pay, Vacation, 401k. Advantages of XO are better life on the road, only super mid fleet, and quick upgrades because guys are heading to Legacies, SWA and dream 91 gigs. Obviously guys are doing that last one at netjets but you’ll have less lifers to contend with.
There are slight differences between 91k of netjets and 135 of XO and passenger expectations. Think Time Share vs Airbnb.
As for WU just think of it this way a couple of xo guys have gone to NJA. A lot of Gama/DPJ/TMC have gone to XO and NJA. And 99% of XO and NJA guys would think about a desk job before going to Gama/DPJ/TMC. Good Luck!