Just stripped and polished my navy blue 2006 Seaway center console boat in October. Nothing is harder to clean than a navy blue boat with salt stains. It would be easier to polish a curbstone. It took me two full days, but the result was a nearly factory fresh boat. I used the Colonite two step process.l purchased it on Amazon. I'm sure,had I been in a hurry, I could have done it faster,but I was in no rush.
I did a sailboat several years ago with a Zep like product. Looked fabulous from a distance (10'). Sold it a year later for my asking price. It still looked good, but the process to remove the old finish and reapply was daunting. Very labor intensive to do the job correctly the first time,and I just removed wax and haze. It would probably require a jackhammer to remove the polymer.