Sir, we were also confused between the two. However, we chose Wagon R for the following reasons:
1. most of the parts are imported
2. Better gear and brake
3. Beautiful interior
4. latest technology
5. Beautiful stereo
6. power steering, front power windows
7. driving position much better. You can see the ground right in front of the bonnet
8. it is much more comfortable
9. pick is better
An amazing thing which i noticed that, with the AC on, if you drive right behind a diesel vehicle, you smell diesel inside the cabin, (true for my XLI 2012 or my previous city 2010). Whereas there is no smell inside the cabin.
I highly recommend it Wagon R.