Laura, I've done the shuttle and I've done the trolley. The trolley was not a pleasant experience. We usually go up and back in one day - live in No. Cal. Last time I went I used the trolley and it took over an hour to get there (you take a bus from the airport to the trolley). Than took a taxi to the doctor for $5. Did the reverse on the way home except it took us about 3 hours to stand in line to get through the border. Than the trolley and all the stops - since we had already missed our flight, we took a Taxi from the bus stop to the airport. Barely made the last flight home. We arrived at 11:30 am and our flight left at 7:20pm (we missed the 5:30 pm flight). We also went on a weekend - but it was cold so we thought it would be easier - wrong! A shuttle would have gone a little faster and we would have been protected from the chilly wind. Personally, I feel safer and more confident I will make my flight by using the shuttle. It is a little more expensive but I feel it's worth it - but it's not cheap. I know people that do the trolley that had a good experience. Again, I think the weekend played a part in it. Either way - make sure you get those fills and check ups! After all - it's your health! Good Luck