My recommendation/suggestion for domestic purpose AC purchase (House utilisation)
1. All brands have second/third party contract system with local service providers. Whatever brand you choose (i.e. Mitsubishi, Panasonic, etc), a guy from local service provider will serve you. So, it depends upon how good your local service provider for your brand. We cannot assure that one specific brand will give you the same after sales service throughout the nation. (Same situation occurs for your phone repairs. For example, HCL Technologies provides after sale services for most brands. So, we can say that your Xiaomi phone's repair is good if your local service network of HCL Technologies is good.)
2. Less parts, more reliable machines. PCB cost (in Inverter AC only) is always an expenditure for your AC after 5 years of operation. Just because of PCB your AC can't be in working condition. (Assume a situation. After 5 years of operation a PCB gone in your AC during summer period. You consult with your service provider and order a PCB of 5 year old AC of a particulat brand. PCB arrives after 10 days. Service provider has some fresh installtions and replaces your PCB after another 10 days. So, you cannot use your AC for 20 days in a hot summer duration. You have already purchased this inverter PC at higher cost compared to long lasting fixed AC. We can replace a phone in the next day if it is not working. But we can't do the same thing for AC because of Piping network, Interior of house and so many other challanges)
3. Star ratings and ISEER are truly useful. But you should know the EER/Power Consumption at 100% level. You can compare inverter AC and fixed speed AC based on their EER/Power Consumption at 100% Cooling Capacity. For Example, here 2 OGeneral ACs have been compared. (Refer images. Also, refer pages 32 & 38 of the attached PDF file.)
a. OGeneral 5 star inverter CET series AC 1.5 Ton having EER-4.03W/W and Power Consumption 1310 W at 100% Cooling Capacity.
b. OGeneral 3 star fixed BMW series AC 1.5 Ton having EER-3.87W/W and Power Consumption 1369 W at 100% Cooling Capacity.
So, the difference of EER/Power Consumption at 100% Cooling Capacity is very less between 5 star inverter AC & 3 star fixed AC. Now you will say that inverter AC will not run 100% all the time. Ofcourse, you will save power when AC runs at lower cooling capacity. Then your cooling effect will be also less. I will choose 1 Ton fixed AC instead of 1.5 Ton inveter AC for a room size upto 150 SqFt. (with lower prices of 12-15K compared to inverter AC).
4. Watch this videos for actual power consumption and cooling techniques between inverter AC and fixed AC. (Watch both videos fully if you have interest)
a.
b.
5. These brands, showrooms and sales person are trying to sell inverter ACs because they have chain of business with your inverter AC. Inverter AC has lots of electronics/sensors (including PCB) for automation and self-cleaning. These electronics/sensors will increase your AC purchase cost. So, delicate AC also needs a professional technician to install and to service. These electronics/sensors will increase your maintenance and service costs later on (ultimately increase in after sales business).
6. So, in the name of electricity savings you are spending much in initial and occuring expenses in inverter AC.
Disclaimer : I am just critising electronics/sensors parts attached to ACs. If you have enough money to spent on inverter ACs and its occuring expenses. Please go ahead with it.