Yup, I would say the worst shonen I probably like was Air Gear, but Oh! Great is, in my opinion, the best Artist in the business so he can make you forgive a lot story wise. Not to do a disservice to Miura Kentaro or Inoue Takehiko, but to me he edges them out, especially considering his consistency.
Nowadays I don't watch much anime apart from a movie that catches my eye now and then. I'm too lazy to look for an original series, and for the manga based anime I just read the manga.