Hi,
They haven't been flow matched that I know of since they are new, but they should be within 4% or better from the factory. You will of course need a chip for the 440's.
Dont know who thats directed to, but the 50's I have were flow matched when I bought them. Been in the car for about 2K miles. They were taken out for the new motor build that demanded bigger injectors. I had no issues with them at all