If anyone is looking to get new Velux blinds. I recommend the pleated energy blinds. They are a big improvement over our old rollerblinds. I think they have also reduced the noise levels.
Have you got more info on companies that supply these blinds? Can they be retro-fitted to existing Velux windows?
The blinds I bought were from here.
They are genuine Velux blinds, I think they fit most sizes but check the plate on the window for the window model first.
Presumably they can also be ordered by size for non-Velux windows.
One issue is that I want a blind for an inaccessible window so would use solar or electric options and then they don’t offer the blackout fabric. Maybe the mechanical option can’t take the extra weight/stiffness of blackout fabric.