No, Hanae Mori HM and Pi are not similar.
There is a difference: Pi is more powdery and sweeter, while HM is a smoother, more balanced scent. If you do get the Hanae Mori HM, make sure you get the Eau de Parfum and NOT the Eau de Toilette: the EdP is the smoother, mellower one, while the EdT is just a cloying floral mess.
As for compliments from the opposite sex: HM wins.
Also, have you tried Angel MEN (A*Men outside the US and Canada) by Thierry Mugler, too? Now that's the gourmand to beat...more compliments, more foody, and (IMO) simply a better scent.