I've lost count the amount of times I've seen him live, in my opinion Sub Focus is one of the best and influential D&B artists around.
Going all the way back to 2009 'Rock it' was released and was the soundtrack to me learning to drive (far too reckless for my own good). I've seen him in Jersey, Creamfields and a few times at Printworks.
I would go as far to say that anyone who's been to a D&B gig will have heard his tracks at some point, a lot of DJ's play his tracks and mix into them as they have really versatile and catchy melodies.
He consistently puts out bangers that are played worldwide, a true modern pioneer of British D&B. I highly recommend watching his B2B Printworks set with Dimension, the best D&B set of all time, I will die regretting that I missed it.