The good:
Layout: Having arrow keys in a nearly 60% layout is like give water to someone in the desert.
Quality: Like a tank, solid feeling, plate mounted switches. There are a PBT dyesub version keycaps that are nice and will last forever.
The bad:
There is no programmability capacity.
The space bar has odd stem positions so it will prevent the use of standard 6.25u bars.
The right shift is 2.25u, thus, you will need two left shifts of the standard ANSI size, that no standard set has.
The window key is 1u, again, standard sets do not have one.
Its size does not allow the use of custom cases
Conclusion:
The FC6660M is a solid keyboard, built with high quality materials, the design is highly functional. However the odd size caps makes very hard to source cap sets, and it does not have macros, nor programmability.
If you want to use it in its stock form it is a great small keyboard in the case you need dedicated arrows. But if you want it to enjoy the customization freedom of MX switches be prepare to make some compromises for the odd caps and mainly with the space bar.
