I use it on my Jomsocial site in combination with AlphaUserPoints and my members like it as well.
It is easy to install and you can customize it also for your needs (design PSD is uncluded).
A great module!
This game is very well coded and has such a professional look and feel that i have to say it is every single cent worth.
What i also would like to mention is that the developer "Bill" is a very kind and active person who is always there if you need help or if you have problems or questions. I purchased another component (Ko! Who's there) from Bill and i use also the free MJ Slots. All his components are great extensions and work like they should. I'm a very happy monjoomla customer.