We love them both. It depends on what you're looking for, as they are entirely different. LTT is a character meal with a "Thanksgiving" theme.
Ohana's has a very festive atmosphere & more of a variety I guess. If you have children, they also have group games at Ohana's to entertain. Also, Poly is a great resort to visit.
BTW we've got adr's for both this year, & have done both twice before.