San Francisco Hilton Union Square

Have just booked 3 nights at the San Francisco Hilton in Union Square. Would appreciate any comments on

• is this a good hotel for a 3-day family trip to San Fran
• what does the complimentary "Starbucks Continental Breakfast" entail, is it just a voucher for a coffee shop downstairs or is it room service

Good location, nice sizeable rooms, although not actually on Union Square and yes, the Starbucks breakie is just as you surmise!