I've used Wrenwood O'Brien for dozens of jobs in the buildings I manage for three years now. Sean and John are always available to answer questions, solve problems, and best of all, deal with dbi bs for me. If there is a callback from a job (which is rare), they always do what they have to in order to make it right. They treat you like a person with real concerns, not just a client that they're trying to juice for all they can like most contractors. The quality of work done for a nominal price keeps me, and my clients, coming back time and time again.
Pros: Friendly, knowledgeable service
Cons: Because they're so damn good, they can get overloaded at times-but they'll get it done