The short answer (and short is the wrong word for this gargantuan squash) is that tromboncino tastes phenomenal as a summer squash and just ok as a winter squash.
Tromboncino, also known as zucchetta rampicante and Tromba d’Abenga (Albenga is a city on the Italian Riviera where tomboncino originates) is a cultivar of Cucurbita moschata, a constellation of squashes that includes butternut squash. Trombonchino, as far as I know, is the only or one of the few squashes in the Cucurbita moschata family that is harvested as a summer squash