Every company claims some xyz or abc unique latest technology resulting in rapid cooling or a few thousands in power bills, sounding very simple & laced with marketing & technical jargon. Do not fall for all these.
Technical Facts are like this: The Refrigerant will be in liquid phase post compression carrying a potential energy to expand at an orifice placed in indoor unit, to create cooling effect, as expansion process absorbs heat from surroundings. The cooled liquid + gas mixture further passes thru expander coils in Indoor unit for maximum heat absorption to become fully gas again before reaching compressor via water or air-cooled condenser throwing away the absorbed heat. Before expansion the liquid is buffered at nozzle for uniform rate of expansion & to avoid phase mixing resulting in lesser efficiency and chocking of conduits. And in household ACs normally nozzle size & compression ratio & rate are fixed. So there is not much scope for ‘Rapid cooling’ etc, except by reducing nozzle size upto a technical limit or employing more nozzles which will need more bigger compressors. Hence more or less all the ACs cool equally rapidly a few seconds plus-minus. (Custom built units have these facilities). It is preferable not to run ceiling fans while operating ACs as they tend to draw hot air from heated or hotter ceilings, which can mix with cooler air that tends to come down being more dense
Secondly veracity of all the claims of Rs. N000 of savings get tested by a measure called EER which is BTUs of heat lifted (divided by) no. of watts of power consumed in lifting that heat. Just see this figure of magnitude (8 to11) say 9 or 9.5 or 10.6 , which is specific to a model of AC, depending on design of various components & technologies employed in refrigeration cycle. In a more simplified manner the Star Rating which reflect the above mentioned facts, has now been made mandatory by the government 1 TR AC is adequate if no wall is exposed to Western side Sun heat (and if the room is with a thermo-coled false ceiling if located on top floor) and measures max.150-160 sft. Thereafter upto 200-230 sft 1.5 TR unit will do and beyond that in multiples. Split ACs can have marginal better efficiency due to different fan types & speeds for Indoor & Outddor units.
Also if you are a seasonal user running AC for 6-7 hrs in the night for 4 months & occasional 2-3 hrs in the day during weekend holiday etc, a star rating of 3 or 4-FOUR will be more than enough rather than paying more for a 5-FIVE star rating which is ESSENTIAL for a continuously run equipment like refrigerators to result in meaningful savings in power costs. The addl cost of Rs. 4-5000 for 1 or 2 star difference in Split ACs will take 5 yrs to pay back as per above usage. Again preferably avoid 2-star or 1 star to save extra bucks, if your usage is on above lines & go for such models only for standby ACs or low usage units.
Hence to summarize, as far as a typical upper middle class consumer is concerned, If the AC is 3-4 starred and if EER & build quality of two models are almost the same, then there is no need to pay more for Hitachis & Daikins except for buying notional peace. Now a days even these brands have brought low cost models by compromising on build quality and I happened to buy Kaze 3 star model. But service of Hitachi is very poor as expressed by many consumers and my personal experiences support that as they are deploying local unskilled boys of AC repairers many times resulting in poor jobs. Infact in case of my Kaze 1.5T model purchased just last season, the Service Manger at Hyderabad refused to provide warranty service within 1 yr from date of installation or 15 months from invoice date, inspite of everything being in documented form and demanded payments for gas charge etc. The people deployed by them have have also broken Indoor unit locks in course of gas charging, resulting in Indoor unit not seating firmly on wall. And inspite of several reminders even on their customer service there is no use for rectification as complaints are simply being closed without attending. And as of now I am still fighting since a couple of months for rectification of the defect.
In all the servicing need aspects have to be assessed at your level from your local networks and friends. But in general aggressive brands and volume players like Samsung etc have better service. And personally I am satisfied with Samsung and Voltas machines in retail category and Bluestar in commercial and custom solutions category, considering all aspects. As far as web posts are concerned Human tendency is generally to be more vocal in expressing unhappiness and poor customer service which agitates the aggrieved user to be more explicit. And we observe very few posts sharing good experiences & happiness; for which one has to take equal amount of extra pains and time to share with other netizens.
Just see the outsized no. of unhappy posts about each & every make & model of gadgets rather than the minority no. posts having anything good to say about something. So rely more on the service experiences in your city/area or friends circle rather than the web posts which can leave you confused, but of course they can be great in terms of drawing your attention to some interesting aspects of the gadget/service. And ACs inddor unit filters need to be cleaned regularly and outdoor condensor unit needs wet wash atleast once in a year. And do preserve all original invoices, receipts and warranty cards till the expiry of warranty on compressor to avail warranty service.
Happy buyer and user experience.