urethane is the best it will cost you more some times 3x as much but will last longer then fiberglass. fiberglass is crappy stay away from it if you can, it is not as durable as urethane, if you hit something minor fiberglass will crack where urethatne bends or flexes.
Installing isent that hard, tools are minor, but that is if it is a lip kit mainly a few screws and some double sided tape.