R40 Upgrading DVD-RW drive, master/slave settings ?

[skript]

hello!

I want to upgrade the dvd-rw drive of my R40 (which still has the original CD-RW/DVD-ROM combo drive). I just want to make sure that I have the following information correct:

1. dvd-drives on thinkpads (R40) are set by default to 'secondary master'
2. in order for a 3rd party drive to work in my R40 they need to be set to 'secondary master' as well
3. the only way to set master/slave settings on a laptop dvd drive is through firmware
4. if a 3rd party drive has default settings other than 'secondary master' then such a drive WILL NOT be recognized by tpR40 and possible firmware change will be needed (reverse ata)

I'm currently looking to buy any of the following drives:

- Nec AD-7543A (default: primary master)
- LG GSA-T10N (default: primary slave)

Does anyone have experience with using any of these drives successfully in a thinkpad ? I would welcome any other advice from anyone who has done firmware changes in order to set the drive to 'secondary master' settings...