I think it's hard for people to believe some of these gimmicky things that dealers offer. I'm not familiar with the treatment, and can't claim to know anything about it. In general, I don't know of any chemical treatment that completely protects for extended time periods. Most likely, it will lose some level of effectiveness over time. Will your car be easier to clean than untreated? Absolutely, but I struggle to believe that anything can perfect for ten years... Especially if it's only guaranteed for five.
I'm glad it looks good, and that you're happy with it. At the end of the day, that's all that matters. Everyone has their own opinions, but it's your car.