Greek: Adscript or Subscript Iota?


I've seen many fonts that use adscript iotas in compound glyphs (Ai, Hi, etc.) but there are many others that use it as a subscript, under the main character glyph. Wikipedia says that the adscript is preferred for epigraphy, paleography or other philological contexts blah blah blah...
I ask to the people that know best the language: greek people. Which one is really preferred in Greece? Adscript iotas or subscript iotas? I think they both look nice but I'm not greek, just a guy making a font.
Thanks in advance!