well.....basically, stay away from fiberglass unless you have to.....
but since most kits are made of fiberglass, and polyurethane is expensive....you usually don't have much choice
but in the end, it goes like this....if you're buying from a shop that isn't a dealer for certain big companies, you're more than likely getting a knock-off, which are molds made of the original fiberglass kits
these kits are usually not very well made, they will crack eaier, are thinner, don't fit well, and need a lot of prep to be painted
in the end, you'll get what you pay for.
if you want to go safe, go directly to erebuni or their dealers to get the real kits
but since most kits are made of fiberglass, and polyurethane is expensive....you usually don't have much choice
but in the end, it goes like this....if you're buying from a shop that isn't a dealer for certain big companies, you're more than likely getting a knock-off, which are molds made of the original fiberglass kits
these kits are usually not very well made, they will crack eaier, are thinner, don't fit well, and need a lot of prep to be painted
in the end, you'll get what you pay for.
if you want to go safe, go directly to erebuni or their dealers to get the real kits