I have used the Goya passion fruit pulp in desserts quite a few times. On the most recent occasion, I found that it was quite sour indeed. Perhaps the product varies from batch to batch, or, more likely, there is a sweetened and an unsweetened version. In any case, I used Lyle's golden syrup (pure cane sugar syrup) for a smooth, quick, and concentrated sweetener. This is a far better choice than granulated sugar for drinks, I imagine. (Lyle's is an English product available at Treasure Island).
As far a fresh passion fruit goes, one of my favorite taste memories involves split passion fruit topped with honey served alongside a flute of prosecco. The good friends and the sunset over a beach in Italy might have had something to do with it, though. So many buzz-inducing factors are hard to separate.
Man : I can't understand how a poet like you can eat that stuff.
T. S. Eliot: Ah, but you're not a poet.