I am flying Business Class from DEL to TLV so this is the only Star Alliance lounge currently operating at Delhi airport.
It is nothing special, the service is friendly and staff come around and ask how is the food and then request me to fill out an online feedback form.
The food is ok. A bit salty. 5 or 6 hot veg and non-veg items.
But the internet is miserable. In fact all throughout the airport the internet is very weak.
So after an hour or so, I leave for a 1-hour walk around the airport, return to have a quick shower, and then leave again to board my flight.