My first trip was in 2009, landed in Beijing and spent the first night in a hotel catering to western visitors.
The company provided a driver who picked you up from there the next day and drove you to a hotel in Tianjin. They pick you up at the hotel each morning to go to the facility and back in the evening. Employees are all bused in from 2 hours away each day in company owned buses. This is the case with most western companies in the area.
The company provides an English speaking guide while at the facility and during any other activities. But when they drop you off at the hotel, you are on your own.
In the evenings I was treated by the facility manager to Chinese dining. He used US visitors as an incentive for his employees hosting group dinners which I found interesting and a great way to try many different foods and learn some culture. These dinners were held in various restaurants usually in private rooms. One person in the group orders from what looks like a catalog and everyone is seated around a circular table with a large lazy Susan. As food is brought in it is placed on the lazy Susan with small plates for each dinner. The plate are not for food but sheer you discard your bones. I decided on the first day to learn to eat with chopsticks.
I have been to the great wall, Tianimin Square, Temple of Heaven, Summer Palace and other sites. Shopped the markets and watched them sting pearls for necklaces I brought back.
I do feel a little isolated while in the hotel mostly because it is impossible to read signs. As far as feeling like I was watched? Not so much but controlled is another thing, internet was very restricted even in the hotel dedicated to western visitors.