IIT Bombay is one of the best IITs in India. It is known for its academics and also for the salary packages they offer. IIT Bombay graduates tend to receive good packages. After receiving your B.Tech graduate from IET Lucknow if you get into IIT Bombay for M.Tech in the CSE branch then it would be really good for you both academically and when you get placed.
The average salary package for the IT sector stands at 18.5 lakhs per annum and it sometimes reaches near the average mark of the CSE department. Hence it will prove to be a good step in your career.