If Bethesda would have had a tiny budget with Oblivion, it would have looked like Dark Kingdom
With all of that being said, it's surprisingly entertaining. The level-up system keeps the player entertained and striving to advance their selected character. You're able to earn new and more powerful abilities and weapons as you play, as you would expect from an RPG. The levels are designed well, though they don't pose much of a challenge.
This is one that is definitely worth checking out, considering the reduced price. You could probably get away with a rental, though, since it should take less than 10 hours to complete each character's storyline.