Pros
CallTower invests heavily in both their communication solutions and in their own employees. Actual time and effort is put into improving the performance and outlook for each employee, with regular goal-setting and job satisfaction review. It's organized, well-managed and company-culture oriented. After working for several companies with no room for growth and poor management, CallTower is incredibly refreshing and rewarding.
Cons
Honestly, I don't have any substantial cons to list. CallTower suffers from growing pains as any successful company in the telecom industry does, but there are active initiatives to address these things. They are expanding the scope of their operations, aquiring new products and solutions, and remodeling their office to make room for more employees.