I admit I'm not a huge reader of the comics, but I've never even heard of Darwin or Angel.
Darwin's only been around for five or six years.
And Angel has only been around for ten now. I want to say she popped up shortly before the last time Jean Grey died, still saying she'll come back any
So it's understandable that you don't know who they are.
Darwin came out of that awful All-New, All-Different X-Men retcon but he's a pretty cool character who has an awesome mutant ability. He's currently co-starring in the X-Factor comic, although he's on hiatus from the team.