I think the question is deceptive.
What might be dreaded for my taste, may be someones best, or even a premium smoke.
I happen to like Onxy Maduros.
As far as I think are dreaded:
Thompson's brand
Flavored smokes
Everything else I have smoked and dreaded, I thought we're good just not my taste.
I am rather new, only been smoking cigars for 9 months. I sure I will run in to some more