I have a pack of 2 Lab40 works in master / slave to € 250.
It's been two months that I have with 2 uses and it is my first lasers.

For that price I'm not disappointed. I've used it in a hall. People are impressed: the goal. It should be used with a fog machine: it is superb.
I think my perspective is not objective

All this remains to product longevity.