However, everybody is copying or porting Solaris DTrace. IBM AIX has a copy, called ProbeVue. FreeBSD has ported DTrace. Mac OS X has ported DTrace. Linux has several DTrace copies - none of them good as the original. Just like ZFS - everybody wants it and has ported it, or copying it: BTRFS.
So, yes the copies are immature and inferior. It is difficult to reinvent superior software as ZFS, or DTrace or Containers or CrossBow or SMF or... - because we see that still today, after many years, BTRFS is not functioning well. Ktrace is not functioning well. etc. All the copies are not functioning well. The ports are functioning well: ZFS in FreeBSD and DTrace in Mac OS X - all works well.
This proves it is difficult to copy Solaris tech, it is so new and unique. It is not just like, a polished version of a software, no they are totally different animal and does not look like anything else on the market. For instance, DTrace was totally unique and revolutionary when it showed up and everybody was baffled. Several Linux devs switched to OpenSolaris just to get DTrace.