Can you suggest a good air cooler. I heard Symphony is the best.
well symphony is good ,if size is not an issue the best cooler they have is the model called jumbo or sumo go.
Kenstar is good too…
Symphony !!..
theres this model at 7800 ..check out compare india
which place you are from? If you are from a humid place like chennai, coolers wont be enough.
on more thing at wats the power consumption of coolers.
i have one runnin almost 12 hrs/ day
Finally i brought a Kenstar-DOUBLECOOL Dx CW - 0121 air cooler, It comsumes 200 W max. It do not have a traditional fan (horizontal axis) but have a blower concept(vert. axis fan). 
THrows air with huge velocity 
bt, noise more than others
All in all a good air cooler.
^^^^lol…I hope you were joking…I dont like coolers as they tend to get the room all humid and half way thru the nite you suddenly feel like your in Mumbai or Chennai instead of Bangalore…I cant afford the $$$ for the extra load capacity I would have to get to run an AC, but I rather not get a cooler.
well i agree but in low humidity places it won’t be that bad,if u are able to circulate fresh air then it will be cool,like if u place it in the window or such way that the intake will take fresh air from the outside.
Atleast far better than Fans
bajaj pc 2500 = Rs.3750/-
Symphony !!..
JUst go for it !
Good.
They are the most effective
Next step would be to get a second hand AC for around 5-6K… 
Thanks man for the wonderful post, it was very informative.! good going…
Another recommendation : Coming from a user:
Position the cooler so that, it can channel air from one direction to another so that the air doesn’t get circulated in round robin. If the air gets circulated in round robin than its going to be hell humid. So make sure that doesnt happen. For e.g. keep a window open (with mosquito net closed) and keep the cooler near the a door (most effective) or window. This will give you good cooling.
~LT