Even one 50K word story would be too long to read fast, unless someone has whole days off. And believe me, I've seen an entry for a challenge at another place that could qualify for a short novel.
Eep! That was me you're talking about! I don't mind there being no word limit, however the author of the story should be aware of how people vote and decide, so a too long story could actually decrease the chances of the author winning no matter how good their story is.