The colours were very drained.... until you switched the box to output RGB and then they were a lot better. I had both in the early 2000s and there wasn't any difference between the picture quality of Sky or Ondigital.
Yes. I had my Sky box looped through the OnDigital box, and you could quite cleanly switch between the two using the AV toggle button on the OnD remote.
Slightly higher saturation on the OnD box, but nothing significant
This all reminds me of the time when I was a kid (sorry if this makes you feel old) and had pretty much memorised the Telewest digital interface. I was at a relative's and did the usual geeky thing of fixing the stretchyvision on the widescreen TV by changing the format from 4:3 cut out to 16:9, and changing the output from composite to RGB (I could tell the difference even then). However it turned out that the TV didn't seem to like the RGB mode for some reason, and I had to own up to messing with the settings the next time I went round
At least it taught me not to mess with other people's stuff no matter how 'wrong' I thought the set up was…
Something that really annoyed me were tellies where the four channels were not tuned in, in the correct order.
About 25 years ago, myself and some friends were staying in a pub in Wales for the weekend, to do some mountain hiking.
The Friday night, after about 10pm we found ourselves alone in the lounge bar. I picked up the remote to find something to watch, and discovered that the 4 channels were completely in the wrong order.
I set about retuning them to their correct positions.
Next day, was Grand National day, we'd been for a hike, and entered the pub about 10 mins before the race was due to start. The bar was packed, and everyone in there was bizarrely watching an old b/w film on S4C. One of my friends clocked what had probably happened before I did, rapidly turned us all around, and we headed elsewhere very swiftly !