I took the challenge from Facebook. I wish I could have more time, I spent around 23 hours, although I had almost 10 weeks for it. The course is very interesting, as they give a lot of code to experiment with. The several methods need a lot of time and computation power, you have to use a public cloud for AI. The course has the scope of image recognition, but it goes further with text recognition with methods that are developed during the last 4 years, such as convolution neural networks and recurrent neural networks.