> I think there was me and others expecting slightly better than
> Atom 1.6Ghz performance

Okay, so you've been wiser than most others, including me :-)

> As it's kind of "mobile" version of G5, it was perhaps silly to
> expect it to perform like G5 or G4 per Mhz...

Regarding G4: Why? The G4 up to 1.67 GHz was used in mobile devices as well.
Regarding G5: You're probably right.

> I should re-try with newer MOS OWB.

Yes, please do and report back.