You probably won't find any creatures that actually use stealth mode in any of the campaigns (don't recall any myself anyway) but there is still value in those skills for all campaigns.
Keep in mind that Spot and Listen check against a creature's Hide and Move Silently (respectively) skill levels so even though they may be using invisibility or sanctuary your toon will still be able to target them with sufficient skill levels in the detection skills depending on the creature's default blueprint (and often customized by module designers, especially bosses). IIRC Greater Sanctuary is the one concealment that cannot be pierced using the Spot or Listen skill set (GS was originally called etherealness which is an unusual form of concealment, but its effect can be sometimes modified by custom scripting).
In SoU, there is one quest in the beginning of the campaign in which Spot has particular value.
But, as you already seem aware, in PvP it becomes extremely important especially against sneakers.
My own rule of thumb, for what it's worth, is to either max them both or ignore them both. The check is still a dice roll so even with low/no skill rank investment, you may still win the detection given enough time (one roll every 6 realtime secs). Also, both are wisdom-based, so typically clerics, druids and monks (for example) will gain significant modifiers by their inherent characteristics.
Check the NWN wiki to acquaint yourself with the nuances of how the mechanics of the skill perform.
...and...
Welcome aboard! Have a great time playing a wonderful and eternal D&D game!
edit: omg... typos galore
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Modifié par HipMaestro, 23 juillet 2013 - 01:42 .