I believe people who pick their own numbers have a slight edge over those who prefer QuickPicks.
Biglooooser is correct; you are at the mercy of the previous players' numbers when you buy a QuickPick. I've tried the suggested experiment, although with different numbers, and he's right; the terminal seems to regurgitate many of the numbers on the previous ticket. When the PowerBall jackpot reaches $80M or more, I'll buy twenty QuickPicks (no PowerPlay), along with the losing numbers I've been playing for the past twenty years. When I get home, I check my QuickPicks to find the numbers I don't have in any combination. Normally, there are between six and eight numbers from the white field which don't appear anywhere in the twenty supposedly random choices generated by the terminal, but there have been rare occasions when I'm missing too many numbers to justify the additional expenditure. When this happens, I usually just go to bed and pray a lot.
Once I've identified the missing numbers, I wheel them to form as many combinations as I can. I then discard any combinations which contain three or more consecutive numbers, so I usually end up with another ten or fifteen numbers to play. So far, I've hit a hundred dollars on five separate occasions using this method, but it's been a while since I've won that much.
I only buy the PowerPlay on my own numbers which, as I mentioned, I've been playing for twenty years. They've never won a jackpot for me, but nobody likes a quitter; when the new matrix is instituted, those numbers are bound to hit together within the next 1.7 million years, as I play every possible permutation. In other words, I use every number as the PowerBall, except one, because it exceeds the upper limit of the red field, so I have five numbers to play twice a week, with the PowerPlay. For a few weeks, I was winning enough to pay for next week's tickets but, naturally, that went away just when I was beginning to think I had stumbled onto something.
People who study the numbers have a decided advantage, in my opinion, over those who rely on dumb luck. Simple statistical analyses can reduce your odds significantly. These can include frequency analysis, positional analysis, grouping, partnered numbers (two or more that tend to hit together), value analysis (assigns a value between -5 and +5 to each number in the field), color-coding or graphing. Even if you're able to correctly eliminate only one number from the entire field, you have a better chance of winning than the guy standing behind you who wants a single QuickPick. Lightning does strike, but how many of us here are willing to climb a tree during a thunderstorm? I think most of us would find the longest metal pole we could find to make sure the... um... lightning struck us... instead of the guy... you know... standing behind us...
(*sigh*)
Okay, so that analogy got away from me a little bit, but you know what I'm trying to say. The simple fact is, the more numbers you can eliminate from the field, the better your chances of winning, and that's true of any lottery game.
If you're going to play QuickPicks, why not take Lazyjim's advice and randomly select the numbers yourself? Overall, I'm sure you'll do at least as well as the machine, and probably better, since it's likely you won't know which numbers the last customer played.