[Dovecot] Performance with 200k messages in Maildir

What should I expect performance-wise if I put 200000 messages in a Maildir store and use two or three MUAs (mutt and Thunderbird), on an Athlon dual core 2GHz with SATA drives in software RAID (Linux)?

Like; would it be useless/crawling, usable or pretty fast. I imagine MUA startup / first time folder read would be slow, but daily use more or less ok.

Thanks to Dovecot's indexing, I imagine I would be better off interfacing Mutt to Maildir via IMAP and Dovecot rather than accessing Maildir/ directly?

-- Vegard Svanberg vegard@svanberg.no [*Takapa@IRC (EFnet)]