I like my Eyedro monitor. It is a dumb monitor, and it doesn't integrate with anything. But it does keep good track of consumption, has some nice graphs, and keeps a long history. It includes a bunch of good analysis tools. It was fairly inexpensive compared to others out when I bought this maybe about 3 or so years ago.
They are currently about $100 for the wired (ethernet) version, which is what I have. https://www.amazon.com/gp/product/B00EP77KZ2
