STR Mumbai pales in comparison to the JW Marriott Sahar. Location is better at STR, but service is heads and shoulders above at the JW. Don't stay in Juhu at the other JW unless you want to be stuck in insane traffic.

Few random experiences at the STR Mumbai - not approached a single time at breakfast, staff using elevator to go up or down one floor while on their cell phones, no drink service at the pool, etc. Also no lounge.

JW Sahar upgraded me both stays to amazing suites, had an excellent pool, phenomenal breakfast spread, fantastic lounge, etc.