This one's at least kind of cute. It makes some use of the reincarnation trope as a framing device for why the two are friends, though I don't know if it does a whole lot. It's also genuine about the princes falling in love, though it's a little awkward to think about how the female leads react to it. It's still enough to elicit a chuckle and is cute in its own way, but it's not groundbreaking.
My ratings on the series, from best to worst:
1-2, 2-3, 2-4, 2-2, 4-1, 2-1, 1-4, 3-2, 4-4, 4-3, 4-2, 3-1, 2-6, 1-5, 3-3, 3-4, 1-3, 2-5, 3-5, 1-1