Better than a screwdriver. The mix of juices seems on point, while the gin adds a subtle juniper note. I felt like this needed a squeeze of lemon/lime and/or a drop of syrup. But the aftertaste made me second guess. Tried it again with Hayman's Old Tom. I liked it better with basic Bombay.
If you want a lighter version, one not so fruity and thick, use a Fresca grapefruit soda or similar…in the states we have Pilar brand carbonated grapefruit/ lemon mixes that are perfect for this drink.
Enjoy