This is a simple but very effective cast cover that I have used repeatedly over the two weeks since purchase. I am puzzled by the few negative reviews since I have found the cover easy to put on and take off. The seal at the knee is watertight but not uncomfortable. I have no hesitation in recommending this product.
As A relative newcomer to Ubuntu and Linux I found this handbook an excellent resource for getting more familiar with using the command line. Whilst still not an expert I can now do virtually everything I need to do to manage my system effectively.