They all seem to have the same role; bump it up the middle.
The one that has impressed me most is JSL. He has really thrown his body into his work and brought some much needed aggression to proceedings.
Hasson was fantastic coming off the bench in the Cowboys game and lifted our intensity, but he seems to be lower in the pecking order.
Lui has been average, without being terrible. He drops the odd ball here and there, but put on a good hit in the Sharks game from memory, I just think he needs to start doing it week in, week out.
Overall, I think the three collectively have been pretty damn good all things considered (injuries/retirements/Kite and Rose leaving etc.).