Complex sentence: Fountain Inn is the "tarnished" part of South Carolina's Golden Strip (one of the fastest economically growing areas in the state,) also comprised of Simpsonville and Mauldin, having not seen the growth and prosperity of its neighboring cities and Greenville County.
Split into simpler sentences: Fountain Inn is the "tarnished" part of South Carolina's Golden Strip (one of the fastest economically growing areas in the state,) also comprised of Simpsonville and Mauldin. Despite this, the town has not seen the growth and prosperity of its neighboring cities and Greenville County.