I wish that they were the biggest problem bug for my tomatoes, but that title goes to the godforsaken spider mites. They decimate my plants every summer as soon as the weather turns hot, and I've tried so many things to combat them.
This year I've applied a couple rounds of predator mites, and in addition to some ruthless pruning of affected plants, I feel like I'm actually holding ground in the battle. Though really hoping that the predator mites will establish a population, as they're a pricy solution.