I just bought one of those from surplusshed and it is big and very nice. Here it's pictured with a equilateral prism from them and my DragonLasers diffraction grating beam fan.
Yes, those surplus ones look nice for those wanting something bigger. Surplus shed always seems to have some too, as opposed to the short term deal in the OP. +rep to crazyspaz.
I'm fairly sure it depends on the coatings used on the different sides of the cube. Most sled cubes have
different coatings on different facets to optimize passage of different wavelengths and filter then direct the
beams where they need to go. These cubes are broadband, so anything from 400 - 650nm would work
even if both beams are the same WL. Someone correct me if I'm wrong. I still haven't played with cubes,
though I definitely want to try someday.
Darn! I placed an order for four of these on the 3rd and I checked the satus of my order today, it said cancelled. I called them up and they said they all sold out real quick and it took their system a while to show it :cryyy: