I've used Discovering Math with my kids, and liked it. Haven't used the common core edition. It integrates pre-algebra, algebra I, II, and geometry into the first 3.5 levels (level 4B is basically review/test prep for GCSE). Discovering Additional Math is advanced trig, some geometry with proofs, in the first half (usually taught concurrently with 3A/3B), and SV calculus in the second half (usually taught concurrently with 4A/4B). We chose to use them sequentially, with Additional Math after 4B. So, loosely, you could view them as 7=1A/B, 8=2A/B, 9=3A/B, 10=4A/B, 11=AM, 12=AM, covering pre-algebra through calculus.
Dimensions Math is the common core version of Discovering Math--similar, but with skills in a different sequence. I'd stick with the original, which is more consistently available from singaporemath.com than from other sources, many of which are switching over to Dimensions. I like the way algebra practice is woven into the geometry chapters, and geometry into the trig chapters. The review exercises are also quite challenging, as are the "brainworks" challenge problems. I've frequently found myself or my elite-STEM-institution-educated spouse puzzling over a problem.
