External CNG fitting is not better

If you want to do CNG externally, don't go for it as I have driven this car 1,56,000 km in 9 years in CNG externally fitted. Headwork is compulsory at every 40000 km and car will vibrate after head work and also off while in full ac with full passenger and become irritating driving experience once it head work comes to the engine. So don't save 75000 rs and buy company fitted CNG as they have used technology to prevent these issues. Don't save 35000 rs through external cng fittings, you will get irritated by car performance after each 40000/- km.