Is this supported? It’s a 2-in-1 Z-Wave switch + dimmer.
http://www.amazon.com/Remotec-Z-Wave-ZDS-100-Plug-in-Dimmer/dp/B009CH9ZWQ
I have a few of these, they work just fine. The only thing about it, at least last I checked, you have to keep the device as a dimmer in SmartThings. You can still flip it to switch on the actual device and it works just fine as far as I can tell.
I see… For a moment I though it really was a “2-in-1” device, i.e. both outlets could be controlled by Z-Wave. 
If only! Not bad for the price really though, since they can be used either way. I bought a few on eBay for around $25.