I use both Qubes and SmartOS (like OpenIndiana, an illumos derivative) although not together. One advantage to using OpenIndiana directly on the laptop -- and I

I use both Qubes and SmartOS (like OpenIndiana, an illumos derivative) although not together. One advantage to using OpenIndiana directly on the laptop -- and I've not tried this, maybe it's too much pain -- would be you should get much more memory efficiency out of zones than you do out of QubesOS. Qubes relies on a type 1 hypervisor (Xen) so it is not nearly as efficient at reclaiming memory as an illumos/Solaris derivative, since Solaris zones are OS level virtualization (they are not under the illusion they have a whole machine to themselves so they are handling memory as flexibly, pretty much, as an application process). Qubes is notoriously memory hungry which can be an issue, especially on an ultralight laptop (the ThinkPad X1 for example still tops out at 16GB RAM which can actually be a little tight for Qubes). (There does seem to be some degree of memory reclamation which I assume is due to hosted OSes and maybe Xen itself evolving over time to respond intelligently to frequent changes in "installed" ram.) The downside I imagine would be 1> you don't get Qubes' security measures of isolating USB and the network stack into their own VMs, away from dom0 and 2> from what I gather there just isn't the same extent of specialized plumbing in OpenIndiana for a single user trying to do work across vms/zones - qubes has for example a little menu to redirect arbitrary usb devices into particular qubes, there is a gui flow for moving files securely between zones with explicit dom0 prompts/approval, there is a secure system for moving clipboards between vms, etc.