That's exactly why it's hard to judge "how long" will X product last. The variables differ a lot. If KSG lasts bi-annually for everybody, Big Berts won't be offering it on their quarterly paint protection program to save on costs.
Opti-coat's a great product, don't get me wrong there. However, the question is whether it fits your needs or not. In my case, it doesn't because it's uncompetitive on price-durability versus well-regarded "long life" waxes and sealants.
I agree sir with the price. What caught my attention was the reviews of Opticoat and its supposed to last protection for long periods of time.
Actually pinagpipilian ko din yan if KAIO/KSG combo or try Opticoat. I thought Opticoat is priced at around 25k. 6.8k lang pala, although pricey pa din.
also compare sealant non-DIY application time & cost x2 at the least vs the Opticoat option. With DIY, it's a no brainer but a good gauge before trying DIY is that you are satisfied and beaming at 8 of 10, better yet 10 of 10 of your DIY projects. Else it is very wise to hand it to the pros. Nothing bad about that. Earn from your expertise, pay for other stuff.