This query will actually can be answered in different - at times confusing - manner by the members. Each one of us have a preconceived notion about the brands. Also choosing a better cooler will also depend on many actual aspects on ground than giving a generalized response. So rather than providing you with a list of coolers, I would prefer to give you a lot tips that can be helpful to you in choosing tho cooler that suits your needs.
Choosing the right type
Coolers differ based on the type of operations needed. If you need a larger area to be cooled, you may need to opt for evaporative or desert type coolers. For your personalized cooling needs or smaller rooms a portable room cooler will be enough. Choose the one that meets your needs rather than going by dealer suggestions.
Pad thickness is of utmost important for better cooling effect. Ensure that the pad thickness is at least 90 cm.
A good cooler should have the options for adjusting the fan speed. Make sure that the cooler you choose comes with the option to control speed. It will help you adjust cooling effect.
Automatic water level controls
The best cooler should have automatic water level controllers. This is to ensure that water is filled to preset levels and avoids flooding.
Automatic shut off dampeners
Ensure your new cooler has thus additional feature. It will help reduce the loss of cooling effect.
Choose proper size
One cannot suggest a better cooler without checking your exact needs. Size depends on the area of the room to be cooled. Height of the ceiling from ground also plays an important role here. A simple formula would be CFM of cooler = (square feet area X height of the ceiling )/2.
After paying attention to the above points, you can opt for any brand of your choice and choose the model based on above points. Go for established brands like Symphony, Bajaj or Usha.
I am not providing a list of coolers available in the market because the choice of a cooler is totally dependent on the requirements on the ground rather than providing you a theoretical best cooler.