Smartos experiences

I'm looking for information is someone running smartos in production environments and what are your experiences (the good, the bad and the ugly) ?

This also includes triton datacentar (private cloud).

I've been investigating smartos (on home/work pc, under virtualbox) and it really looks mature and well engineered.
Looks like the only remaning and maintained solaris derivative (feel free to correct me).

All comments are welcome !

Thanks and regards
Peasant.

Is illumos not under consideration?

@jim Illumos is not an OS (i.e. not a distribution). SmartOS is based on Illumos.

@Peasant I believe other illumos based OSes are still maintained including OpenIndiana Hipster and Tribblix. OmniOS has also been recently "resurrected".