I got 67 keys Mermaid for my ALT. It has arrived long ago. I had time to try it on finally today. This set of Keycaps is the original set of ALT caps. Exact same legend, same material and same quality. If you have CTRL or ALT keyboard, you should be familiar with the caps.
I agreed with other reviews. These caps are not the best quality ones. They are thin (A lot thinner compare my enjoyPBT on another board), not great under RGB backlighting and kind of uneven between caps. However, they are not terribly bad either. I think they are ok caps for the price.
There are two reasons make me give these caps 5 stars.
1) It is not easy to find PBT double-shot backlit keycaps.
2) They match my ALT board very well. Especially, the caps look much better when the backlight is off, compare to the original one. The original ALT caps are kind of dark, the legend is very close to the background color without backlighting, and the texture looks a little bit "dirty/dusty" in my opinion. But this set of caps looks very well.
A picture is worth thousands word:
Mermaid with green backlight:
Surprisingly, the caps went very well with my original ALT caps, which created a different flavor:
Mermaid without backlight for closer look.
Mermaid with pomegranate red backlight:
I strongly suggest who has ALT/CTRL to give these set a try. For the price, I am very satisfied.