Good combination I think. Unerring accuracy one end, more erratic but bowls some unplayable deliveries the other end.Hazelwood is very high quality (better than Starc IMO) like McGrath parsimonious but the comparisons aren't needed, he's made an excellent start to his test career and in various series dominated some world class bats
Starc and Hazelwood are a brilliant combination, if they stay fit they could become an all time great one, things get scary if we add Cummins and Pattinson