^ Just started new game, did it straight away (lv 3) before starting Shivering Isles, because I wanted the sweet gear.
It does take around 2-3 hours maybe more of time, depending on how acquainted you are with moving around Cyrodiil and finding new locations. The battles can be quite tough however, espicaially at one point where you have to defeat nine (yes, 9), full fledged knights, one after the other, very soon into the quest.
That said, the KOTN quests do give you a chance to get into (or back into) the game, give you enough enemies to train on and enough puzzles/dungeons to keep things fresh.
Is it true that the weapons/gear get better when you level up, even if you already own them??