I took the exam at home through PearsonVue. I had a pretty good experience with them, although once you hit question 89 you are given a 10 minute break before you go to the rest of the questions and you cannot go back to question 1-89 once you pass that point.
Ya my scores were the first time I took the practice exams. My strategy for the mock exams were pretty simple, I found reading the question carefully and really understanding what process you are in, what stage of the project your in (initiating, planning etc...) and then what the question wants from you (either an input, tool & technique or output) asking myself these questions for each question really helped me eliminate answers that would not make sense based on the proper steps to take in a project according to the PMBOK guide. Sounds like your doing everything right doing the mock exams and reviewing them was definitely what I focused on the most. Reading the PMBOK guide and on topics I wasn't sure the prepcast elite videos really go into detail on each process.