I've been edc'ing a SE Salt 1 for the past four years. Rips through plastic zip ties and cardboard like crazy! As far as touch-ups on the go, I carry a Smith's diamond sharpener. You can pick them up at most outdoor shops for around $7. The rod is tapered on one end for the serrations, and a flat part on the other end that works great for the little bit of plain edge. Plus, its the size of an ink pen, so I can take it everywhere.
I never worried about having a sharpener with me until one day that I was cutting open a package at work, and I hit one of those big copper staples that were hidden under the brown tape. I ended up with one serration that was bent over.
That one bent serration bugged me all day! So, I decided to start looking for a good portable sharpner to keep in my backpack. Found the Smith's at a local hardware store and decided to give it a try.
For such an inexpensive sharpener, this thing rocks!
John