Reddit mentions of REUSCH 7960 Chelsea Leather Food - Black

Oh hey! Congrats on new boots!

I'm assuming these are another pair of black docs that can take a shine? If that's true, my go-to conditioner would be something light like Chelsea Leather Food. I've heard good things about Saphir Renovateur as another conditioner you can apply polish over - it's a mink oil suspension, but avoids some of the drawbacks of plain mink oil (namely, it doesn't seal the pores of the leather).

Then, if you want a bright shine, it's fine to use up your can of Kiwi, but the next time you buy polish, pick up some Lincoln Wax or Angelus. The former is what the Marines use to get their mirror polish, but it's a bit fussier to work with. The latter applies more like Kiwi, but the shine is a bit more durable.

And, if you want a shine that's a bit less... mirrorey, Meltonian is the best.

Don't forget to clean them each time you take care of them, though—you don't want to be applying any of these over dirt and grime.

Oh, and I don't think the half size large will be a big issue, especially with insoles and thick socks. That sounds pretty comfy.