SCART on the Xbox limits you to 480i so that should be avoided.
Ahem. SCART on the Xbox is only a downgrade if you have an NTSC console. If you have a PAL Xbox, RGB SCART might be a better option. In my tests I found RGB SCART has much more pronounced colours than component. YPbPr seems noticeably darker. The only advantage to using component are games that run in 480p, 720p and 1080i. But Microsoft disabled these resolutions in PAL regions. Even if you hacked the console to output those resolutions, you still need compatible NTSC games to take advantage of them. I software modified my PAL Xbox a few years ago and regretted it. It forced my PAL games to run at 480p and it actually looked WORSE than 576i, full more pronounced jaggies and a generally compressed looking image. Plus at the time I was directly recording with my Elgato, which deinterlaced them to 576p – a higher res than I could get out with the hacked console and the games I had access to.