Gunite has many advantages over fiberglass which is why fiberglass is usually cheaper. Structurally stronger, no flex pipe, Any design and size you want, less chance of pool popping out of the ground Or settling. Finish will last years longer than fiberglass- Some pebbletec pools are approaching 40 years old And still look brand new. Mine is 17 and looks as good as the day it was built. If prices are comparable, go gunite.