I have been using the bit setting tool since it became available. My old Panasonic (5-cd changer) dvd player will not dvd movies on +R media unless the BookType is set to DVD-ROM. I have been using Ritek 2.4x +R media for this very purpose with great success.
My Panasonic dvd player seems compatible with -R media by default, but for some reason the Ritek 2x/4x -R media I have used skips and plays choppy when I burn dvd movies (this was with the FS0F and FS0H firmwares).
The FS0F firmware also has another problem for me. I can't read the end of -R disks that I burn (2x or 4x) with the 411s drive that I used to do the burn. This always seemed very strange to me because I could read the entire disk on other DVD drives, just not the 411s. The read problems seemed to be isolated at the very end of the disks (maybe it was some kind of session closing bug?). This problem was very consistent with the FS0F firmware and seemed to go away completely with the FS0H firmware (that makes me think that the FS0H is better, but I could be totally wrong).
As far as why I want to burn at 1x? I have heard that burning at slower speeds makes the burned media more compatible with more of the devices out there. I just wanted to give 1x a try when I realized I could not.