A lovely way to appreciate apple flavours, and it's good to see Avallen as the recommended calvados as it's an old favourite of this drinker. I used Cawston Press Cloudy Apple juice, in the absence of freshly-pressed Granny Smiths, and it's in UK supermarkets. It's a "monolithic" cocktail - but definitely something that adherents of apple might like to explore.
The generous portion of pear juice hides a kick from the vodka and is subtly boosted by the sweet Triple Sec and sour lemon juice which are, no doubt, fighting it out in the background, but without actively altering the dominant Pear flavour. In the absence of agave, I used sugar syrup - sweetness can be down to personal taste - 7.5 ml suited this palate. A fascinating alcoholic take on a plain pear juice, with added oomph, edge and intensifed flavour!
It's intriguing that different reviews find different flavours to the fore. I agree with John Hinojos that the sherry & vermouth are more pronounced (used Martini Extra Dry). I added an extra 5ml elderflower for sweetness and to accentuate that flavour aspect. A great aperitif for those who can't decide between a plain sherry or dry vermouth and desire the best of both worlds plus elderflower & subtle lavender.