Thanks Jools - yes, you've exactly identified the ones from the two different groups! I think I will look to sell the green lasers, as the LFS I got them from isn't the sort to admit they have got something wrong. Much as I like them, I really wanted a school of just one single type and would worry ...

Thank you, that's really helpful.

All were sold to me as gold laser, but the group from one LFS have a different tint to the other. Or are they all gold laser and just two different breeding lines? Group 1 (? Green laser) are the larger ones, in the group on the right below. Also attached a video of the ? Green lasers and a solo ...