The red arils are sweet - very sweet for some varieties. Too slimy for my taste when fresh, but I've eaten a few of them dried. We added some dried arils to rice once to give it color, but it didn't add much to the flavor.
I think bitter melon causes a lot of people to be apprehensive.

Justifiably so, IMO... its definitely not for everyone. It is very good for health reasons though, especially for diabetics. Of the more unusual vegetables in my collection, bitter melon gets the most attention - hence the avatar. I have 6 varieties in the collection, and grow 2 varieties every year (but 3 this year). Besides what we eat ourselves, we have quite a few Filipino and Asian friends who use bitter melon in their diet, and we give a lot away to them each year. Finding a way to successfully pickle bitter melon is my greatest culinary challenge.
The grand children have all been fascinated by the bitter melons hanging from the vines - especially when Grampa told them they were "frog cucumbers".

It really is an interesting plant, and would be a conversation piece as an arbor cover.