Interesting thing happened last night, I brought about 7 bats I wanted to sell to cricket nets last night, and a guy picked out a bat that he liked the look and pick up of, and bounced a ball on it and said "This bat has no ping". Now of course, I was slightly offended as I like to think that I wouldn't be trying to sell duds to anyone, and funny thing is, I have one of his son's bats in for repair (plays for Scotland) which was fully knocked in, and the bat he had picked up responded pretty similarly with a ball. Considering the bat hadn't been knocked in at all, I can only assume that it will get much better with some time with a mallet. However, I think that picking a bat on ping alone is not a good way to go about it, as each plays in differently and each one is pressed in a different way depending on what the maker wants to achieve. Also, the fact that his son had been using a Newbery GT Players which responded pretty similarly shows that the ping of a bat and how it plays are two completely different things. Should also mention that his son also came to look at bats, and he based everything on pick-up a feel, and didn't choose by bouncing a ball on them, simply because they didn't pick up the way he liked his bats.
I picked up every GM bat in my sports store the other day, and they all sounded exactly the same, as in they all had a planky sound. Then come the next day, my friend brought a GM Flare he had found, very well used, but the sound off the mallet, ball response and pick up were all incredible. I think initial ping is a very misleading thing to judge a bat on, and all bats need to be given time to be played in. If we are so worried about ping in this forum, why do we buy Lavers? Because we like to give them time to play in. If you are like me, and like to use/buy lots of bats, I would say initial ping is somewhat important, but if you stick to 1-2 bats a season, then always, always pick a bat on pick-up and feel.
IMO, it's very hard to tell a bat is a complete dud, which is why some companies, even the boutique ones, end up selling duds. It's just wood in the end, and I reckon that if the batmaker knows it is a complete dud, he will cut it down to a smaller size and sell it as a junior bat or something like that.