I used Ancestral Attic several years ago, and was very happy with them. We sent them the info that we had on our own beforehand. Based on that, they set us up with personal guides in each city, and helped arrange our itinerary.
We knew my husband's grandmother was born in a small village outside of Warsaw. The guide picked us up at our hotel and drove us to the village. Having her with us was invaluable! Depending on how far back you want to look, the best place to find records in Poland is at the local churches. The priest at the church where my husband's grandmother was born spoke very little English, so we needed her to help translate. We discovered while at the church, that this was a "new" church and that the original building was currently being refurbished. The priest drove us to the old building, unlocked the padlocks on the doors, and let us go in. It still had the wooden benches for pews, and the dirt floor. It even had the original baptismal font which is where she would have been baptized. We were able to find all of the original records of the church, showing births, deaths, baptisms, etc.
We believed my relatives were from the Poznan area, so they also set us up with a tour guide there. We didn't have a lot of luck with that church, but our private guide was equally good.
We enjoyed our time with our guide from Warsaw so much, that she has become a good personal friend, and we visit her every time we go back. She is one of the most knowledgeable people you will ever find about Polish history.
It is very difficult to find records in Poland, so don't be disappointed if you go and don't find a lot when you are there. It's an absolutely beautiful country though, so enjoy your time there.