Buying a AC is no easy task, With so many brands to choose from and varied reviews of each if you ask the Dealers or check online.
Try to go for Split AC , they are much quieter and more efficient though come at a higher Initial Cost. The Hitachi window I have makes me feel like sleeping next to a running vehicle !!!
The Total ownership cost difference over 5 Star rated and 3 Star Rated AC over a course of 5 years is almost same usually. But 5 star rated AC’s are about 20 % more expensive than 3 Star ones when buying the AC ( but this 20 % is paid back over 5 years in most cases). You can check using the calculator below.
More expensive does not mean itll recover its cost in Electricity Bill as some companies state. Do the calculations yourself and you will see.
Avoid the Cheapest ones out there, there is a reason they are cheap !
Most big terms like AntiBacterial filters, Night mode,Ion Purifiers etc are nothing but terms to attract you. You should just look at appropriate cooling capacity and running costs. As most of us just Switch them on and forget about them.
Here is a small calculator I wrote based on a Thread from TechEnclave which will help you check running cost of an AC and the total ownerships cost over a period, use the calculator below to decide if the AC is worth the extra money or which one is better -