I used J pear liqueur (60 proof) and not true eau de vie. Quite tasty, indeed; the maraschino didn't have a chance to dominate. Powerful sweet. The only real drawback I can see is the risk of diabetes. 4/5.
Yes, I would not substitute Pear Liqueur without re-designing the drink. It would be way too sweet for the amount of acid, and would overpower the other flavors, since Pear Eau-de-vie was a much more subtle flavor.