Just a clarification since I can no longer edit my earlier post.
I've finally found out what the pen I mentioned (the cheap 3-4 EUR clone of the Delike Alpha) brand name likely is. I was looking for the latest Qigong Delike when I saw on some Asian pages what seems to be the equivalent (in looks and price) of this cheap clone. Not being fluent in the languages, my (mis?)understanding is that the brand name is "C3". They also seem to make clones now of the Steel Kaweco Sport/Delike Alpha and of the colored AL variants, although only the Steel variant seems now to be available on eBay in joint ads with the brass version.
That said, although these C3 clones have become my EDC (one with an F and another with an EMF FPR Flex nib) -they are always in a pants pocket-, I'd have to say that my current other favorite is the Kaweco Liliput Copper, closely followed by the metal Kaweco Sports (AL Stonewashed and Brass).
And for over 20+ years, it was a Montblanc Noblesse/Slimline, which was single-handedly my main pen, coupled with a super-slim pen that most likely was a Sheaffer Slim Targa (though after 30+ years I can hardly say if it was or if it was a clone since it didn't have any identifying marks).