Gliptone
http://www.liquidleather.com
Brillant stuff, the paint seats into the cracks and wear. Leaving it look new again. Top notch!
Used 500ml for covering sport seats (a few coats), still have half bottle left.
The best way is to take the seats apart and cover each part, so they don't stick to each other.
There is leather filler (for deep cuts and cracks) on the furniture page. Going to give that a try.
I get some pictures up.