The composer series was designed as a home model spinet. It is not necessarily conducive to playing classical music because it is a spinet, and it does not take the pounding usually associated with hard rock.
It does not contain any of the favored Hammond features from the older series. There are a couple of forum members that have one, but since this is a lower-end LSI model, it has no special attributes or value. These can require some work to bring back to near 100%, even if used only lightly or not at all. After all, these are ove 30 years old. How would you feel about a 30+year old computer? Connectors will need cleaning, leslie oiled, possibly other issues.
If you like it for what it is, buy it and enjoy it. Do not give more than a couple of bucks. My Aurora from the same era is far more feature-rich, and it was $50. 144 is neither a reliable workhorse or a cash cow.