I recently bought the Celerio CNG Vxi. You must target the LXI. It's really a good VFM car. It's spacious and has a dash and steering right out of the Maruti Swift, making it feel like a much bigger and premium car. Also the Celerio is really refined and a good performer - Thanks to the Kseries engine it sports. Low on maintenance and great on mileage with a steady chassis that allows for some good triple digit cruising on good roads (Mumbai Pune expressway)
Pros:
Looks much better than other Maruti Cars in this price range.
Awesome FE
Good after sales service and resale value years from now.
Feels big in the interiors (Beige and black dual tone) and exteriors too. Thanks to the body designs and the 14" wheels.
Drive is peppy and refined.
Brakes have a really good bite.
It's just about 20k more than the WagonR but really really worth it. Rear seat can easily accommodate 3 healthy passengers!
Great ground clearance.
OHM and Really big Boot(y)
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Some nifty safety features. (Maruti is improving)
Oils changes and maintenance interval is 10k kms.
Cons:
The A pillar is a bit too thick and can obstruct the view while taking a turn.
Accessories are missing to keep the price low. Almost everything needs to be purchased separately. (although this can be taken care of by negotiating)
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Rear wiper is only available on the Zxi variant. Not even as an option on other variants.