Ah now, there's the question - what does one regard as 'decent'.... but I would say it depends on how robust the juices are. I can't, myself, see a WOW being very substantial without some grape juice. On a different tack, I made two flower wines this year - Dandelion and Marigold. The Dandelion had WGJ, the Marigold didn't. On racking, the Dandelion was far nicer than the Marigold. Keep us posted, will be interested to know how you get on if you decided not to include grape.