I have had much better luck since I started using Firefox instead of Chrome to run PC. Firefox seems to run much faster for me and I have been able to run 7 or 8 Pandas with almost no PRE's vs. running max 3 Panda's on Chrome and getting constant PRE's. Also, running PC on the new MTurk site has also made a difference. However, I would agree that everyone's results are different. There are a number of factors to take into consideration and there is no right answer for everyone. Mac vs. Windows, running TM/HS/etc. at the same time, browser type, PC on MTurk New Site vs. Old, RAM memory and internet speed are just some of the factors to take into consideration. Experimentation is the key.