The DVD/CD optical drive in my Inspiron 8600 is starting to go intermittantly bad on me and I'm looking for a replacement/upgrade. Dell wants $100 for a REFURBISHED replacement. I'd like to get an upgraded drive (DVD/CD burner with Blueray), but am unsure as to what specs to look for. Newegg/Amazon/Tiger Direct/etc... have several to choose from, but I don't want to buy unless I'm relatively sure it'll work/fit in my laptop. Any suggestions or recommendations would be greatly appreciated. The existing drive is a Hitachi U5251, 24X CDRW/DVD HLDS DMOD.