It's a neat passage. Some neat stuff to see, side spurs and hikes. There's a bathtub with a bunch of blue marbles at some point; lots of local lore in that area. Eureka dunes just past that is worth the trip right there.
If you head in through Saline Road, then in at the bat rock road sign, you'll end up at the hot springs. There's camp spots right there around the first spring, but just a bit up the road on the left there's a little mini "ridge" and the first spot is a nice place to camp with a touch of a west wind break, without other spots on top of you.
Snow or not, I don't think you'd have any issue with it. There's one little stair step part, but it's pretty mild.
This guy has some neat trip info; scroll down and he's got steele pass and the swansea gordo trail.
http://www.gbr.4wdtrips.net/I also recommend the book "Death Valley SUV Trails" by Roger Mitchell; I found it at Barnes & Noble. It has great info about the Saline side and that region. Make a side trip to the salt tram with your camera.
Also check out deathvalley.com. The forum there has good up-to-date road info and there's a link to the Death Valley MOrning Report, a pdf put up every day with condition info.