External CD-ROM Driver for X 40 ?

[ThinkPadX40]

which chose is the best ?

If Original IBM seller is the best solution choose below one;


ThinkPad CD-RW/DVD-ROM Combo II Ultrabay Slim Drive[+$143.10 ]

IBM USB 2.0 CD-RW/DVD-ROM Combo Drive[+$251.10 ]

IBM USB 2.0 CD-RW/DVD-ROM Drive[+$269.00 ]

IBM USB Portable CD-ROM Drive[+$161.10 ]

and ThinkPad Multi-Burner Ultrabay Slim Drive[+$349.00 ] is the CD-ROM ?