ABC Ltd. utilizes a complex manufacturing process involving multiple stages. The company allocates overhead costs based on machine hours for the machining department and direct labor hours for the assembly department. If the machining department incurred $200,000 in overhead costs and operated for 5,000 machine hours, and the assembly department incurred $150,000 in overhead costs while working for 7,500 direct labor hours, calculate the overhead allocation rates for each department. Assess the implications of using multiple allocation bases on product costs and profitability.