Here is today's Lemon cucumber harvest. The camera stripped a lot of the red out, it seems.

They seem ripe. I know the pictures on websites all propagate this look for some reason, but at that stage they are just as ‘good’ as any ripe cucumber, full of hard seeds, hard skin and a softer texture. They need to be picked pale green and the shape is the most telling, it should be somewhat oblong and not round.
The advantages of this cucumber are the tender-crisp texture, thin skin and good plant vigor, if picked on time. The downsides are low production for plant size, those very many spiky hairs and that scar tissue at the flower end.

I think I'm actually allergic to them (but not other cucumbers), but my relative likes them so much that we grow them anyway. Every other year we've grown them, they've had tiny plants, with just a few fruits per plant, but this year the plants got huge and produced a lot. This is the only year I've ever fertilized them, though (and they had a trellis). The Muncher cucumbers didn't do very well by comparison, this year (fertilizer notwithstanding). The Armenian cucumbers did well.