Both of the projectors that you are considering will do NTSC and PAL progressive.
If I'm not mistaken, I believe the Sony 127x series projectors have more zones for zone convergence than the 125x series. This makes it a lot easier to tweak to attain perfect convergence. This is obviously important in movie watching so that the picture appears as sharp and detailed as possible.
I have the Sony 1271 and I believe there are 32 zones of convergence. (I don't really count, I just DO it!!) I believe the Sony 125x series have 8 zones.
The 1271 can do interlace or progressive. However, without a transcoder or the component video input board, the only way to get progressive into these projectors from a progressive DVD player is through the RGBHV input. Most people use an Home Theatre PC (HTPC) to output a software DVD player through a video card such as a GeForce or Radeon. This delivers a teriffic progressive picture (all video card output is progressive) and also gives you the opportunity to max out the resolution of the DVD by increasing from the max 480p output of most standalone, progressive DVD players to a higher resolution. I have seen most people claim that a 600p resolution is the "sweet" spot for the Sony 1271 producing a film like image withoug softening the picture.
There are also some makes of some standalone DVD players that can output RGB such as the Skyworth and the Malta(?). They are not normally sold in the US and must be special ordered. Search for those brand names on this forum and you should be able to pull up more info.
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