My NB has been some form of DW+2h build for AGES, and yes it's very much viable. Typically you will use the 2h bar for buffs and debuffs, and the DW bar for combat.
PC/NA
Envy Me - Sorc
Kutsus - NB
Kutsmuffin - Temp
Kutsuu the Destroyer - NB
Kutsuu - Temp
Natsu Dragoneel - DK
Kutsumo - NB
depends on what you wanna do. For leveling and solo play, yea it makes things easy, survivability is high, damage is okay-ish. Might be a good pvp setup but idk im a PVEer
if you're ever considering to be competitive in vet dungeon or trial dps, consider DW/bow. When both of these setups are played to their full potential there is just no comparison whatsoever, there will never be a single scenario where 2h/DW wins, or even comes close for that matter.
DW/bow or 2H/bow also works very well for PvP. Sticky PvE talking you will want a bow though. Poison Inject + Volley are two skills that will increase your DPS by a lot, so much they're must have.