I had a new CT200h for 25 months, during that time I covered 38,000km (23,612m) and it returned 61mpg Ave. Including 2 trips to uk and around northern Europe, also trips to Dresden and Slovenia.
The IS 'Mr. Jingles,' is now 16 months old, has 22,244km (13,861m) on the clock and is returning 51mpg Ave. Including 1 trip to uk and 2/3 to northern Europe. I found the CT too hard a ride so changed to the IS. I am happy with the change and with the mpg achieved in both motors.
I use 'Fuelly' and 'Spiritmonitor de.'.
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Hi Venkat
I posted the above in May this year, as you can see I drove up hill and down dale, even across water! The CT is a good motor and very reliable, a good place to spend time, but for me and many others, it was too hard a ride. I changed to the IS for the better ride, and it is. If, as you suggest, it is going to be used a lot, I would recommend the IS, it is an even better place to spend a lot of time, with more comfort and almost noise free, + the Lexus reliability. The economy is a little less than a diesel, but it's more than made up for in respect to comfort.
Yes, as stated above by Geof. and Paul there are many things that affect economy, I could add more, driving a Hybrid takes a little getting used to, but once mastered, can give good results. It is a personal choice of course, might be a good idea to test both if you can for a day.
Good luck whatever you decide to do.
Best wishes.
Michael.