Service PAM000 by Panerai or watchmaker?

[Gigaton Punch]

I purchased a used PAM000 (Calibre OP 1) that has not been serviced since its initial purchase (nearly 6 years).

Is it worth getting this thing serviced by Panerai? Or should I save the cash and get it serviced by a competent watchmaker? Any risks in going with a competent watchmaker (such as testing for sealing and water resistance)? Finally, what are the estimated prices for getting it serviced by (a) Panerai, and (b) competent watchmaker?

Thanks!