There is a lot of confusion about whether juices are good for you but it really depends on what you put in it.
Firstly, I would always recommend a good quality blender. It doesn’t have to be a Nutribullet by the way, there are lots of other less expensive brands on the market that do just as good a job! The difference between a blender and a juicer is, when you use the blender you consume all of the fruit or veg. A juicer leaves way too much goodness (fibre, vitamins & minerals) behind.
The next important factor is ensuring you are not just using fruit. Too much fruit will give you a massive sugar spike so it is important to get the balance correct and ensure you have vegetables and fats in there too!