Which brand of AC should I buy? This is a million dollar question.
There are many top brands available in the market. Each of them is good in its own way. Making the choice is difficult. It depends on a lot of extraneous factors. Naming any brand should not be the right way to go about it because different people have different choices.
Let us take a pragmatic approach and look at things from a broad angle.
Product reviews matter
It is always a good thing to do your homework before embarking on the task of purchasing an AC.
You will have to contend with various confusing terms like BTU/hr, BEE Star ratings, EER, and so on. Going through the product reviews will let you understand the meaning of these terms. Hence, you will be in a better position to judge.

Secondly, these reviews deal with numbers. Higher the star rating, the better is the AC. This is the thumb rule. However, there will be many ACs with similar numbers. You need to learn to read between the lines. Hence, this article should be of help to you in deciding which brand of AC.
Customer reviews matter as well
Customer reviews can be of great help in choosing the right brand. Remember, these are reviews from people that have actually used these AC units. They are definitely in a better position to comment on the vital aspects of the AC units. One should pay more attention to the negative reviews more than the positive ones. This is because people might not always post reviews if the product is good, but they do so if the product is bad.
These reviews do not deal with numbers. They are actual experiences. Hence, they are a better tool for determining the brand of AC units you wish to buy.
There are three categories of AC manufacturers, the specialist, the generic, and the inexpensive. Let us look into each category individually.
Inverter technology is better than conventional compressors.

Conventional compressors consume more electricity because these motors run at constant speeds to help the AC attain the set temperature. Once the air conditioner reaches the set temperature, the compressor stops functioning. The fans take over to maintain the temperature. It starts working again as the room heats up. This process continues as long as you keep the AC switched on. This frequent switching on and off of the compressor causes spikes in electricity usage. Besides, the compressors work at full speeds whenever they switch on. Therefore, they consume more energy.
The inverter compressors are different because they do not function at full speeds. Instead, the compressors gradually pick up speed and enable the AC to achieve the set temperature. It slows considerably to maintain the temperature levels but does not shut off completely. Thus, the variable compressor speed makes these ACs consume less power.

Today, advanced AC technology like digital inverter technology and triple inverter technology are available that are highly efficient. For example, the latest Samsung and Haier AC models offer triple inverter technology.
Read: Types of AC Inverter Compressor
Convertible AC is a good choice.
Convertible AC is a new concept where the AC works at varying capacities (tonnage) to provide optimal cooling and consume less power. The ACs work at varying capacities from 40% to 120% according to the cooling load, user preferences, ambient temperature, etc., to deliver optimal performance.
Thus, a 1.5-ton AC can work as a 0.6-ton AC if required. Simultaneously, it can function as a 1.8-ton AC if the cooling load is heavier. This convertibility feature uses sensors and ensures that the appliance consumes less power overall.
For example, LG offers 6-in-1 convertible ACs, whereas Hisense and BlueStar offer 4-in1 convertible AC. Samsung has 5-in-1 convertible ACs. Almost all AC manufacturers provide this facility in their latest brands.
Read: Does Convertible AC Save electricity
Two-in-one ACs – offer heating and cooling solutions.
The top AC brands in India, like Voltas, LG, and Daikin, offer hot and cold AC models, where the same appliance doubles up as a heating solution in winter. This appliance works as a regular, convertible AC during summer to cool the room according to user preferences. On the other hand, these ACs function as room heaters during winter to make them comfortable. So these ACs are known as all-weather ACs.
Smart ACs

Technology has improved today, whereby you can control and operate air conditioners using your smartphones through specific smartphone apps. Moreover, such appliances are compatible with Wi-Fi. So you can operate the AC from remote locations. Besides, it is possible to monitor its usage and conserve energy.
Stay clear of the cheap brands
Cheap brands compromise on the quality aspect that affects the efficiency a lot. The manufacturers of such brands indulge in all sorts of marketing gimmicks like “Buy One Get One free”, and other attractive discounts.
They are available very cheap, but they do tend to consume a lot of electricity. This increases the operating costs of the AC. Therefore, it is not advisable to go for such AC units in spite of the aggressive marketing techniques. One should always take the capital cost as well as the operating cost into consideration. Over the life of the AC, these cheap ACs cost more because they consume more electricity. They require higher maintenance as well.
Read: Best Air Conditioner
Inference
Various factors go into the choice of brand of AC. If you have the money, it is always better to go for the specialist brands. The generic brands are also advisable. Nevertheless, one should be careful about the inexpensive brands. They can actually cost you more because these units consume more electricity.