I saw previously people asked questions regarding using Advance parole. I am here to share my experience with our brothers and sisters.
I used AP twice already this year. One time in Feb and the other time in March.
Documents you need to bring with u when using AP to return to the states as listed below.
1. your passport
2. all AP copies with you.
3. I suggest u to have your I485 Receipt and I140 approval notice with u too.
4. Pay Checks will not hurt. An employment verification letter will be good. But my experience is that those two things are not that important, they never asked that in my cases.
Additionally, I would like to share my experience of using AP with everybody here.
I returned from Beijing to Chicago during the first trip back in Feb. At Beijing International Airport, I was asked to provide my driver license and one copy of my AP to the airline stuff (United Airline) and they faxed it over to US Department of Homeland Security to verify if the AP is not fake and still valid. It took them about 20 minutes to get the confirmation and then they let me pass through the chinese custom. At Chicago airport, I had no problem at all to pass US custom. But it indeed took the US officer quite some time to stamp and sign my APs (about 10 mintues). Back then, that was my very first time of using AP and I had two copies of Advance Parole and the officer took back one copy and left another copy with me. The officer only asked me one question and that is "do you work here?". I said "yes" and then he let me go. I was not brought into another office for further questioning. By the way, you still need to fill out an I-94 form when u use AP. This time, I passed US custom through the Citizen/Permanent Resident line.
The second time I use AP is on my return from Beijing to Newwark in March. This experience is a little bit different from the first trip. At Beijing International Airport, the airline stuff (Continental Airline) did not fax my AP to any US agency and they issued me a boarding pass right away. I had no trouble at B.I.A. Once the flight arrived at NewWark, it took me almost 50 minutes to even reach the custom officer's desk. There were not a lot of people waitting to pass the custom that day. I feel that it takes officers there longer to do the inspection work. Anyway, when it was my turn to talk with the officer, again, initially, he did not ask me any question. It took him maybe 1 minute to scan my passport/visa and take a look of my AP. Then, he asked me to do the fingerprint and took a pic of me. Then, he asked me the same question "did you work here?". I said "yes". He also asked "what type of job do you do?". After the second question, it seemed like he was ready to let me go. But what actually happened next is that he pulled out a plastic bag and put all my paperwork into the bag and told me "follow me". I was brought into another office (I should have called it waitting room). There were at least 40 people waitting in there. He explained to me that his colleauge is going to input my I485 receipt number into the system to check if the case is still pending or valid, it is just a normal procedure. So, I waited. It actually tooks them probably two minutes to verify my case, but I waited for almost another hour because there were a lot of people in there. When it was my turn, he asked me a few questions. "How did you get the advance parole?", "what type of job did u do?" and "how long have you been working for this company?". Those questions are easy to answer. I actually joked with the officer a little bit. He is a genius and he spoke 4 or 5 different lanugages. Anyways, at the end, he told me that I will have to go through this normal procedure until I get my greencard.
I personally feel that if you have been maintaining you legal status from day 1. Using AP is fairly safe.
I hope my experience will be helpful to you guys in the future.