I have been a big fan of the Wild Hare nylon gun slips for 20 years or so. The nylon is quilted so it provides a reasonably adequate amount of protection for in the trunk and on the course. I very much like the Wild Hare spring clamshell opening that is that is the primary closure. There is also a small Velcro closure wrap that is handy to allow you to hang the slip in a closet upside down.
They come in two lengths (or at least last time I bought one they did). I use notched chokes, and they don't catch or tear the internal material. They also breathe, at least a little bit, as I have never picked up any rust on any guns, even when in the case for a couple of years.
And they also have a handy over the shoulder strap for easy carry on longer walks. They take up less space than a foam slip, by far.