With the somewhat new WDK integration into VS you can deal with VS solutions and projects, I think.
SE is able to import them as workspace/project(s) and you should be fine and you could use SE as usual
You can use VS just as a more or less convenient configuration tool.
AFAIK the kernel debugger integration into VS still lacks important features so you won't miss it.
BTW SE2013 already supports windbg based debugging.
In the sense of upgrading SlickEdit note that SE2014 (v19) provides VS2013 support.
So I'd recommend to upgrade to SE2014 if you don't profit from annual maintenance, yet.
HS2
PS: Please note that I'm guessing. I'm currently not involved in a driver project.