I gave it a try (500 ml bottle, added about 80 ml per tank fill), but didn't really notice anything ground breaking.
Mind you I was having fuel pump issues and probably I'm in terrible need of a new Distributor Cap and rotor (old one *ONLY* has 180,000 KMs).
I'll give it another try again once I get all the 'bugs' worked out.
Regards,
---- Robb -----