I just purchased tickets on roughly this routing for December. I was looking at flights in the December/January timeframe, and prices were running around $1300 for economy and $3400 for business. Obviously the prices vary with travel dates and routings; I did recently see some much lower business fares for travel in September. You can also probably get some much lower fares going through a consolidator. Coming from the US, my favorite time to visit India has been the winter, since the low temps are what I consider quite comfortable and the high temps are what I consider tolerable. Personally I find May-July to be a little too hot and humid for my comfort level.