Yes, I used PACER several years ago. We had put an offer on a house that was selling as a short sale. We took a risk and moved in, renting it, assuming it would go through. Only later we found out that the house had two (2, that's two) secondary mortgages on it...So the house fell into foreclosure. Fast forward to the day of the Sheriff's sale: I went down to the courthouse to monitor the sale (we still wanted the house). The house finally comes up on the docket, and the bidding is about to begin, and....oops, the sheriff says audibly, "Nevermind, the owners declared bankruptcy this morning." (Sale was off...). Boy was I pissed, since the owners, the people with whom we were negotiating this whole time and paying rent to, did not deem it necessary to forewarn us. (Yes, I know they were not legally obligated to give us a heads up, but we had only shown good will and were taking damn good care of the house since we wanted to buy it, and buying it would have released them from a very undesirable financial situation.)
Anyway, that's when I found PACER! I was able to closely monitor the status and documentation of their bankruptcy. All publicly available; all free. As you indicated, I kept my visits to the PACER webpage to a minimum so that I wouldn't be charged a fee. Now, because I knew who all the lawyers were, and because I knew all debts that were owed, I was able to pester, cajole, and convince all legal and realty entities on the seller's side that we were serious about buying the house. It worked. It took two years, but we ended up buying the house. (The main reason THIS was house we wanted: location, location, location.) Trust me when I say I learned the true meaning of fortitude and prayer.
I have nothing but good things to say about PACER!