Udacity's ND used to be amazing, their Self-driving Car ND was the single greatest online course I've ever taken in my life. Sadly, they now dumbed it down, made it 2-term (original was 3-term). There were some issues with other NDs where marketing was not translating to real experience, such as AI ND, where 2nd term was so dumbed down it could be finished in a weekend, or the late changes to Robotics ND 2nd term that removed a real robot from the plan and instead offered academic discount on Jetson TX2. Also, Deep Reinforcement Learning project's scope changed massively for worse (instead of robot walking it turned into moving a robotic arm). Despite these warts, where else could you get intro to bleeding edge frameworks like TensorFlow/Keras/PyTorch 2 years ago on complex real-world problems (self-driving car, 3D object recognition etc.)? They simply had no competition there, but that market might be too small. Coursera/edX is way behind the curve with their academic courses.