The current price of $.30 to $.31 is probably a good entry point (it is a low low). If it goes up 10% (if you put a lot of cash in) to 20% (if you were very conservative with your cash you put in) in the next few days I would sell and take my profit. My advice is don't hold more than a few days or you will likely be dissapointed.
This stock has lost 99% of it's value since it came out of bankruptsy, so even if you take a position at todays low of $.30 now and hold with the intention that a year from now it will be $.70 well I would very strongly advise against it.
Just my opinion of course and I'm sure you are a lot smarter than I am. I did not say money can not be made with PEIX, just don't buy and hold thinking great things are going to happen my friends.
And this is exactly how the resistance levels get even stronger, when everyone put sell orders in the very small range around already formed / identified resistance levels.
But stock market is cruel place where individuals play solely for its own interest, and getting out just below the prices he advises to everyone else, before reversal begin :)