Wirelessly posted (iPhone 3GS: Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_2_1 like Mac OS X; fi-fi) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8C148a Safari/6533.18.5)
OP is planning to keep the RAM to make it 12GB (stock 2x2GB + 2x4GB from third party)