When it was first released, the camera was indeed an abomination. Subsequent updates and even W10 TP have fixed a lot of the earlier issues. It's not a 1520, not much is, but it's leagues better than either a 640 or 640 XL. I've owned all of these phones so my critique is based on actual usage, not what some blogger wrote. Up until the 950, the M8 had the latest and greatest processor on any WP device. Where you'll truly notice the difference between the M8 and any other WP device is when you're you're updating apps, downloading new ones and setting up your phone's contacts, email, etc. It flat flies. No matter what you throw at it, you'll rarely ever see "resuming". That alone is worth the price of admission.
Let's face it, with the app gap the way it is, a Windows Phone needs to be a speed demon no matter what. If I wanted to live with lag, I'd get a Samsung Galaxy.