I purchased WagonR Lxi 1.0 on 22nd Dec 2010. Drove 330 km sofar.
Mileage:
I made full tank at 79 km meter reading and then went on long drive on highway from hyderabad to Bidar and reached back to hyd when meter reading was 323 and did tank full again and I am able to fill 15.07 litres. This gave me a calculation of 323-79=244/15.07=16.19 mileage kmpl on highway(before first service)
I stay at outskirts so you can treat it is completely highway mileage.
we were 5 elders and 2 small kids in this ride. with 30% of AC for 1/3rd of the journey since weather was so pleasent that AC was not required throughout the journey
I have to check city mileage and will do it in few weeks to get some accurate mesasure.
Comfort: good space and new interiors are far better then older version of wagonR. Good at 80-100 speed however above 100 speed looks not stable but for a family car this is fine.
Will check again after 1st service probablay I may get 1 or 2 kms more on a litre.
Happy to receive comments and questions.
Thanks
Raja