If you’re staying in or near downtown, definitely consider taking the Metro from Lambert. It’s efficient and cheap. My cab from Lambert to the Central West End was $ 40 plus tip. I could’ve spent $ 2.50 on the Metro and gotten off at the medical center and walked a few blocks to my hotel. If only I’d known. However, I did the reverse. On my way out of St. Louis, I walked to the Metro and had a nice ride to the airport. Absolutely no problems whatsoever and got to enjoy the sights of the city along the way.