I would say it's just "ok." It's easy to automatically five-star the popular works from many years ago, but read this while keeping an open mind and without the bias of the centures of culture related to the Frankenstein myth and you may take a different view of it. It has some glaring holes (the "instant" discovery of animation, the way the monster can follow his creator anywhere, the inability of Victor to realize what the monster meant in regards to his wedding night..these things were awkward distractions for me. Mary Shelley had a remarkable command of the language but in the end keep in mind she was just 19 years of age. I find no penetrating commentary on much of anything here, and won't be talked into looking for it because the work has perdured.
I'm a huge fan of classical literature and I know this is a classic. Having said that, although I am a fan of 98% of what is considered classic, I simply do not enjoy this work. Whenever that happens I consider it to be a lack of comprehension on my part, because after all - it's a classic!
What happens in this book? Dorian has a painting made of him. His psyche spirals downward but is manifest by the deterioration of the painting, apparently not him. That's about it folks.
There are far too many deeply penetrating studies of the human psyche to spend your time on. Reach for a Russian classic. Reach for something, but I'd move this one to the bottom of the stack.