Tried the variant with fino sherry, which was pleasant but nothing to write home about. Probably something more full bodied and richer than Dubonnet would take it further than 4 stars, eg vermouth Di Torino or Cynar? Or the older Dubonnet with higher abv.
Tried shaking for a change and as a novelty: stuck with the above 3:4 ratio tho with a 47% gin so perhaps cheating slightly 😉. Very light, fresh and fruity, and slipped down very easily!
I didn't like this, but I didn't think it tasted particularly strong. My wife, who is a gin drinker and generally prefers a stronger alcohol taste than I, liked it but thought it did taste strong. I'm not sure what to make of that. Either way, it's decently well balanced, simple to make and looks good.