I read the reviews prior to bookings, and they were right. The lose reviews were from those who primarily failed to read the instructions on where to meet [just on the Mexico side, near the Information Center].
The walking tour was exceptional—Alex made us all feel like welcomed guests. As we walked the city center area, we were exposed to most items tourist typically buy. So I thought I had the opportunity and time to purchase all that I wanted to buy. We made a lunch stop for tacos, a tequila tasting stop, and lastly, a drinks and appetizers stop. The trip was well worth it. Our tour guide Alex, has my solid recommendation!