I was tempted to try Warung Gili because of the reviews here and I wasn't disappointed. The first day I went on my own and had a delicious Ikan Kelak Santan - spicy coconut fish (slightly reminiscent of Thai fish curry) NB I opted for the "not spicy" version and it was pleasantly potent. The next day I dragged along my son who has sampled chicken satay throughout the island. His verdict was 'good' - great chicken but satay 'too peanutty'. I suspect he was loath to give it top marks because of his reluctance to do something as uncool as eating with his mother! His friend reported that his dish was delicious. The main dishes were mostly 20,000 and the boys reported that the beers were cheaper than most other places too.
There are no signs to Warung Gili but it is only about 5 minutes walk from the port. This is the easiest way I found. Head right if you were coming off the boat to Sunrise Resort. Take the tiny little alleyway to the right of Sunrise and follow signs to Scallywags Mango Resort. Warung Gili is just before Mango Resort.