Thomas Shey
Legend
It's been more than thirty years since I've read the Amber series. I don't remember the Merlin stories being bad, but I do remember preferring the Corwin stories much more. Zelazny is an author I just don't hear a whole lot about these days, but he's been dead for about thirty years now, so maybe that's to be expected.
Honestly, the worst complaint I have with the Merlin stories was the power creep, but other than that, I thought a lot of elements of it were interesting and explored areas you didn't (probably couldn't) see from Corwin's point of view.