Whether it's worth it is up to you. I personally enjoy doing all of it myself - some folks don't. I took the PSI course, took the re-cert 3 years later and then the O2 cleaning PSI course. I have a dozen tanks (myself and my two boys dive) so in addition to now having more knowledge of what gets done, I can do it myself. I have my own VIP and O2 stickers - with my ID # on them and have never had them questioned - both locally and west and northern coast of florida. I ended up getting this because of a tank being wrongfully condemned - before that I was happy to trust my LDS (that trust is gone, however I do trust my current LDS, but now it's trust but verify). The O2 cleaning is a lot of work, VIP's not so much unless the tank needs a heavy tumble. Also took the valve repair course, so it's nice to tear it all down, ensure it's super clean and put it all back together and KNOW how it was done and what was done. I got my regulator serviced one time and had to fix the diaphragm when I got it back. Had it serviced by another LDS a year (maybe two) later and they asked when the last time it was serviced as the orings in it were very old - so now I service my own regulators too. So until I had a bad experience, I thought the experts were the way to go. Now, I ensure it's done right (at least to my standards).