If you juice, you'll still end up with something that has most of the fiber removed, is mostly sugar, and spikes your blood glucose just as severely as store-bought juice. Sure it'll have a lot of vitamins and minerals, but straight up blending is generally better, or just eating the fruit/veggies whole.
Depends. I juice up 1.5lb spinach, chard, kale, 1 carrot, and a lemon. I rarely add high glucose/fructose fruits. Carrot juice is pretty sweet. I like green veggie juices over fruit juices.
A real good juicer goes a long way. It changed my perspective the first time I tasted a fresh cup of what I describe above. Invigorating and healthy.