I've never been to LTT, but my picky 7 year old has declared the grilled cheese at Kona the "best ever" and all 5 of us loved our food there in July. The atmosphere is kind of cool, too. There are a lot of selections, and the staff is very accommodating if you have special requests. Plus, the desserts are just to die for.
My girlfriend and I really liked Kona. It takes a little while to get there, even though it's on the monorail, but we really enjoyed the break. If you're not in a hurry, I would definitely recommend it, and we took the opportunity to walk around Polynesian to see if we want to stay there some time. It's also a good opportunity to ride up front in the monorail.