I used the autoglym product on the seats in my GTV as I knew I would be keeping it a long time and it was not garaged, and I found it very good. Kept the leather supple and pretty clean (I did not need to use the cleaning product as such), and gave a nice smell for a while after it was applied. I didn't follow the same practice on my Brera's seats as that car was garaged (and it was leased, so had only a relatively short time with me). I will be treating my Giulietta's leather though as that is another long-termer even if garaged.
I can't really comment on restoring leather.....
Alfa History: 145 1.7, GTV2.0, GTV 3.0 V6, Brera 2.4 JTDm