I stumbled across a stainless steel Ilsa 1 cup travel model in a thrift store, and it works great with dark roast.
Pre-boiling the water and letting it cool a bit before flipping is definitely the way to go.
A strong rich flavor, compared to immersion brewing in my french press and aeropress, but not quite as strong as my moka pot.
I think astringency comes from using too-light a roast in this thing.
Dark roast definitely works better for me.












Supposedly the ideal extraction temperature is slightly below boiling point, about 90-95C if I remember correctly. Thus letting the water cool a little after boiling.
I rotate through all of my brewers, so I don’t get bored, because I only have 1 bag of grounds at any moment for freshness reasons.
The brewers all make different tasting brews, and even different feeling viscosities/textures, from the same grounds.
Out of all of them, I like the taste from my Cucumella the best.