3M Finesse-it is great for hulls that are already in good shape. For older or more oxidized hulls, a more aggressive compound gives better results. The longevity and shine of a wax job is more related to the surface prep than it is to the wax. I've used Finesse-it for years with good results. It's expensive, but it works.
It's essentially what's referred to in the detailing arena as a glaze; e.g. it's a final finish. If the surface has a gloss to start with, Finesse-it will bring that shine to its highest level for a "wet" look and mirror shine. But it won't offer protection against UV. It's only a polish. It needs protection.
Gelcoat on boats and the finish on cars can't be compared; they're completely different surfaces that require very different approaches to detailing.
Gelcoat is more subject to oxidation, and as the surface ages, it oxidizes faster. Oxidation creates micro fissures in the surface. Those fissures break up reflected light and the surface appears dull. A wax job on an oxidized gelcoat fills in those fissures and creates a more reflective surface (shine), but the uderlying surface remains uneven and the coating soon erodes from UV exposure, washing, saltwater, etc. and the dull appearance soon returns. The remedy is to polish the surface to even out the micro fissures by removing the peaks. That requires an abrasive. The more oxidized the surface, the stronger the abrasive required, sometimes wet sanding. There is no shortcut to a good shine. Once the surface is restored, wax or other protective coating creates a film to resist further UV attack and prolong the reflective properties or shine. Some last longer than others, but all will last longer on a polished surface since the coating will be more uniformly even on a microscopic level.
As my hull ages, I've been using Presta gelcoat compound. It's a bit more aggressive than Finesse-it, and is less expensive. Use of an appropriate polishing pad makes a difference, the manufacturer recommends a black & white wool compounding pad that works well. You'll need a polisher with enough power for the task. A Makita 9227 is a choice of many, it has a slow start to avoid slinging polish, and a constant speed control that mantains the rpm over a range of load. It's WORK! It takes me a minimum of 4 full days to polish the whole boat, and as the boat and I both age, it takes longer every time!!
I'm not a fan of Collinite, it seems to get gray with time. I've used Permanon, I was disappointed. 3M Imperial marine is OK, but Rejex is my favorite. Use Polyglow at your peril. It's easy on, looks fabulous, then it gets gray, flaky, looks awful and impossible to remove. Your easy on will be paid for in spades when you try to remove it. Horrid stuff.
That shine is a lot of work, and there are those who'd rather spend the time sitting or enjoying other pursuits. To each his own. But the path to "the shine" has no shortcuts. Except with plastic or cash!
