My rating system:

*****: Joliet Jake (an all-time favourite)
****1/2: Elwood (excellent with just some minor flaws keeping me from rating it 5 stars)
****: Curtis (great stuff, recommended)
***1/2: Ray (always a good listen)
***: Maury Sline (good, but not something I'll play often)
**1/2: Sister Mary Stigmata a.k.a The Penguin (average, boring or not entirely my cup of tea)
**: Bob (disappointing, 1 or 2 memorable moments buried beneath a lot of forgettable stuff)
*1/2: Tucker McElroy (irritating, hard on the ears)
*: Mystery woman (awful, not even worth the costs of packaging)
1/2: Gruppenführer (unlistenable, give it away as a present to someone you don't like)