Like many others I have been trawling through different extensions looking for a good membership/subscription-type service. This one is a very well-designed product that does the job simply and clearly. It doesn't have a mind-boggling array of features which to me is a good thing as I was finding many similar products to be far too complicated for my needs. However, there is an active support forum and the designers seem keen to listen to suggestions and help you to tailor their product.
I was particularly impressed with the support team. I had an issue initially when I installed it and and they responded immediately and sorted things out for me.