Loot is definetly important in Mount & Blade, as even after you've got lordly armor and masterwork weapons for yourself, you still need to equip your hero followers, who generally use different gear anyway. Besides, past a certain point in that game, leveling takes FOREVER, so if you find equipment that lets you take 1 more hit or score 1 more kill, it's still a welcomed improvement.
In general, I'd say yes, as long as the new items are interesting enough to set them apart from whatever you've got currently. Like when I beat some bandits in FO2 and found an M60 on one of 'em (when we were all armed with SMGs).