I did this too. I don't know what model I had but it was one of the noisier units, bought in summer 2007. It started stuttering and freezing every now and then, so I bought a new arcade unit last week, added in my old hard drive, and sold my old unit today. It cost me 20,000 yen for the system and I got 6000 yen for my old one (it has no wireless controller and didn't have the docs, plus the box was ripped on the inside so they took off 2000 yen, the fucks). I wanted to get a wireless controller anyway, which is around 4000 yen, so it basically cost me 10,000 yen or about $100 to swap it out for a new one. Not too bad.