Just for a few months. ;-)
I'm working very hard on ZFSguru today. Past half year I modernised the system architecture side of ZFSguru, with new system images and addon service packages with a better infrastructure. But today the focus is shifting back to the web-interface and probably in december I can release the next version sporting really easy Samba permission handling through drag-and-drop interface. But there is more work in the pipeline which will get released either end of the year or early 2014. It probably will make ZFSguru by far the easiest ZFS platform to operate.
I'd say even today ZFSguru is probably the easiest ZFS platform. But it is not finished and lacks many advanced features the more mature FreeNAS and NAS4Free distributions do offer. That said, ZFSguru has a unique architecture and doesn't use nanoBSD or other frameworks. This allows for more flexibility and unique features like Root-on-ZFS and many others. So the platforms NAS4Free and FreeNAS are much more mature and have more features, but also lack features unique to ZFSguru.
The good thing is that you can switch ZFS platforms if you so desire. So just pick your favourite ZFS platform and stick with it until you desire something else or run into a problem. The most important thing is that people shouldn't be afraid to run ZFS; it is by far the best method of data storage available to us. And it can be very easy; just pick your favorite ZFS distro!
Cheers,
Jason