An update. I hope you'll see this.

You do not want to swap to the stick. I did an upgrade and writing to sticks seems to be _very_ slow.

Sometime my system (running on the stick) just pauses ~5 s. I think this is when iceweasel is writing its
history or whatever it does.

Upgrading with aptitude seems to pause ~15 s (or more). I think this is because the system has a lot of
dirty pages to write to the stick, and while it's doing that it won't do much else.

So my prediction is if you swap to a stick you'll get very choppy behaviour. (My systems has a lot of
memory so I haven't any swap activated, so I haven't seen this.)

But if you have enough RAM so you don't need to swap and don't write a lot of stuff all the time, mining
on a stick works fine and is (most of the time) fast.