[Scottie22]

It's for painting cars and other things, but usually I use a"proper" leather colouring agent at around 60 or 70 quid,
but this paint was only £5.99.

As I said I did not actually "paint" the leather, but used the paint to colour it. The difference is in the technique used to apply it.

When I sprayed on the paint, I then worked it into the leather with a brush and rag, so the paint does not "sit" on the surface but is absorbed by the leather.
Like you say it has done a good job.

I have so much leather to experiment on, and I did a lot of dyeing before I finally did the seats.
I scratched and scraped with my thumbnail to try to get the colour to come off, but it wouldn't, as it had been absorbed correctly.

Bit of a long winded answer, but hopefully may help!