I've been hired by a conversation school for one day a week for a 6 month term. I can definitely say that it's better than being an ALT.
Pros:
Teach people that actually want to learn English
Plan your own lessons, and you're in charge of the class
Get to know the students better
Not having to deal with telling the students about your country's holidays or be forced to enjoy telling them
Meet a variety of people of different ages, backgrounds, etc.
Cons
Work nights and weekends
If the class fails, it's your own fault for not presenting it better