Rebiopsy when the PSA is going down amd HI-PIN in first biopsy?

I am 59 and have had ups and downs with my PSA over the past few years and also had a 12 core biopsy in Dec 08, which came up negative except HI-PIN was found in 2 cores.  PSA history since 2000 is as follows:

2.5 2000; 2.6 2002; 4.5 2007; 6.1 5/2008; 29.23 11/08; 15.1 12/08; 9.0 3/09. I am back in single digits and feel great...  still one doc wants a rebiopsy right away while another has said a 12 core biopsy is good and a quick rebiopsy is not statistically significant according to the latest research, and with the PSA going down... continue to do what you do and get another PSA in three months, then decide.  I like this option yet am curious about the wisdom. I would like to know if similar situations are out there and how you handled them.  This whole business is annoying to say the least. Thanks.