Milter-greylist

Hi to all,

milter-greylist seems mature but I'm wondering about scalibility.

I'm thinking about deploying it for some 10.000/20.000 existing
email addresses (4 SMTP mail-gateways).
Will milter-greylist work in such a context ?
I'm worried about memory needed/usage and performances ...

At first before consider setting-up milter-greylist I'm trying to identify known
partners/mailing-list mailservers to whitelist to avoid
delays with important messages.
No performance problem with using a hundred "domain" statements ?

Do any of you some special log analysis tool (sma ?) to get such information
and do email traffic analysis ?

Regards,

SL/