Checked it way back when it first dropped. A lot easier to grasp than CK2 (which I love) and EUIV (which I tried but didn't grasp me enough to actually learn). Being Paradox there is propably quite some paid DLC out now, but it was a nice game, had quite some fun untill end-game, which had some kind of crisis with interdimensional beings that wasn't quite balanced. Most likely this has improved but I can't say anything about that.
For me the best thing to do with games like this is download it illegaly and if you like it it enough and checked out which dlc you like/need, buy.