Answer to "How do I upgrade the memory on the 12GB model?"As i said , you don't have to use SATA everytime u want to upgrade your hdd. U can use their memory drive and if it doesnt fit te ps3 hdd place , u have to use a kind of credit card(expired) or smth like that.i used my old pc storage and succeeded. Good luck!
Answer to "How do I upgrade the memory on the 12GB model?"No1 liked Sony's idea creating a ps3 with flash memory (12gb) You can use and external hard drive but it will cost u money so... I recommend u too use the cheapest bracket which is the 40gb i think . It's good for storing game file directories but not meant for huge games but still worth it .Dont worry if u have a low hdd on ur ps3. Other method is: Instead of bracket, u can use an 2.5 inch SATA drive, mostly found on pc or laptops,they vary accrording to their RPM. 5400 rpm is enough for ps3. For further help, use youtube