For me, it's homemade strops using (the larger size, slightly cut down) paint sticks from HD or Lowes, wrapped with a single layer of thin denim from old jeans. For compound, my favorite is Ryobi "H" white compound (discontinued but still available on the big auction site and maybe elsewhere). It seems a bit more aggressive than the green chromium oxide Bark River compound which I had previously used (and still use occasionally for a very fine finish). I also have a denim-on-paint stick strop with Mother's Mag applied, and as you can imagine, it's good for when you want to shine up an edge. Finally, I have one bare denim paint stick strop which can be helpful in cleaning up any remaining micro burrs. I also have a couple of different types of strop with 1 micron diamond compound, but since the vast majority of my knives are of softer steels, I don't use them much.
In addition, I have some "traditional" paddle strops---leather on beautiful wood---and they definitely cost a lot more than my virtually free homemade ones. But they don't work nearly as well for me and I have way too much tendency to slightly round the edges with them. That said, they do work fine for the purpose for which I originally bought them---Bark River fixed blades with full convex grinds.
If I had to pick just two strops, it would be the one with Ryobi "H" and the bare denim one. Ninety percent of the time, I'm using just these two or else the Ryobi "H" one by itself.
I became aware of the simple, cheap, and effective denim-on-paint stick strops, along with the Ryobi "H" compound, several years ago from David (Obsessed with Edges) and decided to give them a try. It looks like he may've moved on from there and strops less in general, but this still works well for me.
Andrew
