Basically they are an independent bottler trading into different market areas with different brands - I've tried whisky from all but one of these companies and been impressed with everything they do. They can be a little pricey but the quality is always very good.
The brands I've yet to try is The Blended Whisky Company, they sell a range of three high-end blended whiskies - The Lost Distilleries Blend, The Half-Century Blend and the XL Blend, but thanks to Ros at Atom Brands I'm able to try the last one on the list.