Here is an update about my p-shot experience:
Beside some flacid length gain, I got no gains for BPEL or BPFSL (update: Actually, I just measure myself and I did gain 0.5" in BPEL since first shot!) but I haven't done any length exercises because of my frenulum condition.. Injury takes forever to heal... (whenever my frenulum allows it, I'll do some serious stretching with the Ultrasound device)
I went for my second p-shot last Thursday. Getting a second one was ridiculously discounted so it was a no brainer to take it.
Here is what they say about what to expect in terms of gain from the p-shot. They say that you get immediately enlarged due to the injection in the first 3 days and then gradually come back to the original size and then you are going to regain that first 3 days enlarged size in the following 6 to 8 weeks.
This is consistent with my own observations from the first shot.
For the girth, I basically got 1/4 inch gain per month (per p-shot). So right after coming back from my second p-shot, I was at 5.5" girth. And that is probably what I'm going to end up at in 6-8 weeks from now.