Had my 2nd post treatment PSA (@8 mons), came in at 0.7. I was 2.1 at 4 months and was initially thinking that it should have been lower as the guys I keept in touch with from treatment were at or below 1.0 at 4 months. Like everything else with PC, we all respond differently.
Although I'm very pleased with how I'm doing, a good friend at work just got the bad news and I'm afraid he will have a much harder road. G10 with all cores 100%, bone scans show presence in skull, sholders, upper/lower spine, hips, knees, lymph system. He had to go in right away and have part of his kidney and bladder removed as he had tumors there that were causing him to urinate blood. I find it disturbing that his PSA was 32 and he'd been working with a GP for 2 years (that had him on his 3rd round of antibiotics for urinary frequency issues) who had never mentioned PC to him or referred him to a Uro for a biopsy. Just find it hard t believe that he's known about me and my treatments for the last 2 years and he didn't get it caught until it was out of control. 
Tom