I love this tracker. It's no doubt one of my top 3 preferred ones. And I'm not even that much into ebooks
What sets it apart is the community. People are very lovely and helping. When you join you will probably get thousands of bonus points as a welcome gift that will ease your first days to build your ratio. Speaking of ratio, if you're not going to upload, another very effective way to gain bonus points is by seeding as long as you can, wich is pretty easy for ebooks. Once you have a few hundred seeding you'll earn tons of points.
But ultimately the ratio does not really matter on MaM. The aim is to buy VIP status and then all VIP torrents are free