When it comes to the question of best cooling the ac brand name comes in an Indian mind comes is Hitachi.It cools very good and durabilty is high.As fully copper pipes are used repairing can be done in case of leakage at low cost and chances of gas leakage is low compared to lg, samsung, bluestar, voltas etc.And cooling is more efficient thus saves power.Inverter ac is more comfortable as it runs constantly so neither overcooling and warming up by cutoff occurs as in ordinary air conditioner.But the problem of Hitachi is service for a repairing.I had a remote controller problem in warranty.I had to call atleast 10 times to the call centre after which they replaced it.After that it is running ok.I chhose Hitachi for a reliable and good cooling and power saving efficient ac over the other brands.