got myself a seasonic powerangel and test some rigs,
it reads 95%~99% in PF for the computers with the following power supplies:

1. seasonic S12 380W, (approx. 55W, 56VA~ at idle)
2. seasonic S12 330W, (approx. 44W, 45VA~ at idle)
3. Morex mini-itx 60W, (approx. 13W, 14VA~ at idle)

should i be happy or...?

Yep, it's OK. Power factor should be close to 1.

i have two groups of PF data measured, one group is super high and the other (2 oldies) is around 57%.

i just searched the google and i found this article "PFC decoded" http://www.dansdata.com/gz028.htm , it seems reasonable for a guy like me who doesnt know about electrics and stuff.

Those super high are PSU's with active PFC and those with ~57% are with passive PFC or without PFC.

At a pitiful 0.57 I would expect that to be no PFC at all. Passive PFC would probably improve that to about 0.7-0.8.

95% PF from an APC PSU, you should be unhappy.
APC PSUs usually claim 99% PF

99% is at load, under idle conditions say < 100w its often 'only' 95%. Keep in mind at < 100w its a only a watt or two extra. Same as claimed efficiency, its always at load (say 50-75% or something). some are worse dropping as low as 80%, eg.
http://www.silentpcreview.com/article742-page5.html