In reply to M. Edwards:
Agreed, Great Zawn is absolutely fantastic, a privelidge to climb there...Gogarth has so many more routes though, including spectacular locations like Wen Zawn and the scale of Red Walls, Mousetrap Zawn etc.
Bosigran is a fine crag for climbers climbing up to VS and E2 upwards. There isn't loads for the HVS / E1 climber at Bozzy, and that is the grade range where Gogarth would outscore heavily, Gogarth, Britomartis, Scavenger, Strand, Dream of White Horses to name just a few...