I assumed you were getting it for the look. Since BSS and the sigiled shields look nearly identical, I suggested the cheaper one. If you want to quit, just quit. If you want something to "protect your value" while you leave, I suggest Dragon Bones instead of a shield that could be replaced by another high level shield. 25m won't get you very far in most skills. Prayer, Construction, Herblore, Crafting, Smithing, and Summoning would each cost more than 50m to get to 99.