Sanj, it would be interesting to see what your results are, I have been using optimax since I got my car last year, however I have never got much over 30mpg. A while ago I was doing a lot of motorway commuting and even then on average, bearing in mind I would still do a fair amount of driving round town too, I would get around 27mpg most of the time. Recently I have been doing mainly driving round town, getting down to 24mpg some times. However today I reset the ECU, and in the new year will be going back to motorway commuting everyday, so like yourself I am hoping to see some improvements!
Cheers
Matt