Gold Class has a nice shine but it is not very durrible and it is a cleaner wax. Read more about cleaner waxes in my article.
#26 High Tech yellow also has a nice shine, and it lasts alittle longer.
Meguiars is a good consumer grade wax. Its cheap, easy to obtain, has good results. When compaired to the enthusiest targeted waxes and sealants, it does fall short. The high shine, high durribility waxes/sealants often cost more and require more work. Because of this, the average person looking to buy some wax would most likely pick the cheaper easier wax if they were on the shelf next to each other. Where people who are willing to put the extra time and effort for better results, have no problem ordering off the internet/phone/mailorder.
The reason why wax effects the shine of your car, is because it reflects light differently than bare paint. So, if you think logically, two coats of wax/sealant on your car is going to effect the light more than just one.
This is why acrylic polymers are great for appearance and duribility. They have the ability to be layered one coat on top of the other. Each coats provides more shine and protection.
Some people beleave that you can layer carnauba wax, but I have yet to see any difference from several coats of carnauba. I am under the impression that since carnauba does't cure like polymer sealants, adding more wax is just mixing it in with the old wax, instead of putting a layer on top of it.