Choi GJ, Kang H, Baek CW, Jung YH, Woo YC, Cha YJ. Anaesthesia. 2014 Nov;69(11):1258-65
A review of 9 randomised controlled trials suggested that clinical performance of i-gel was similar to LMA, save for leak pressure and fibreoptic view, both of which favoured i-gel.
Link to abstract