I checked with Alex before buying it, and he said it's a good match.
It sounds good. As many do, I boost the mid a bit as its "all 12oclock" sound is a bit scooped.
Other than that, it's great. The sound of different instruments comes through nicely. Some say that the bottom end is boomy/mushy, but I didn't find that to be the case, which could to be to do with the cab, who knows?
The tone does lack a bit of the richness that the valve power amp gives, but I suppose that's to be expected. The weight and volume (my valve amp is 100w) advantages are huge.
I'll still use the valve amp for smaller gigs and recording, but I'm tending to grab the Streamliner for more and more gigs.