I made the Takumi Watanabe version with fresh raspberry syrup. It is superb: light and fruity, but with lots of complexity. The whiskey and vermouth integrate well with the fruit juices to give a really interesting fresh drink.
Pleasant, but basic. Exactly what you would expect from the three ingredients. Not an example of "greater than the sum of its parts" . Needs top quality ingredients. I used Glen Grant 10, and home made grenadine.