dovecot - Jan 2011 - Upgrade from 1.2.16 with sieve/managesieve to 2.0.8 with pigeonhole

Hi,

I would like to upgrade my server from 1.2.16 with sieve and managesieve 
to 2.0.8 with pigeonhole. Will I get all functionality I was having 
before? Should this migration be painless or will it require some 
additional work?
I've read the Upgrading guide so I know I need to create an additional 
user. I've migrated the mails from Maildir to dbox in the past (using 
the convert plugin); does that mean I'm fully dbox or am I in a 
maildir-dbox hybrid situation? I've noticed that there are still some 
maildir-formatted mail (e.g. 1259960330.M322229P62710.mail,W=2195:2,S) 
in some of the maps.

root at mail /usr/local/etc # dovecot -n
# 1.2.16: /usr/local/etc/dovecot.conf
# OS: FreeBSD 8.2-PRERELEASE amd64  zfs
protocols: imap imaps managesieve
ssl_ca_file: /etc/ssl/cert.pem
ssl_cert_file: /etc/ssl/mail.crt
ssl_key_file: /etc/ssl/mail.key
version_ignore: yes
login_dir: /var/run/dovecot/login
login_executable(default): /usr/local/libexec/dovecot/imap-login
login_executable(imap): /usr/local/libexec/dovecot/imap-login
login_executable(managesieve): /usr/local/libexec/dovecot/managesieve-login
valid_chroot_dirs: /var/spool/vmail
mail_max_userip_connections(default): 50
mail_max_userip_connections(imap): 50
mail_max_userip_connections(managesieve): 10
verbose_proctitle: yes
first_valid_uid: 5000
first_valid_gid: 5000
mail_privileged_group: mail
mail_location: dbox:/var/spool/vmail/%d/%n
mail_executable(default): /usr/local/libexec/dovecot/imap
mail_executable(imap): /usr/local/libexec/dovecot/imap
mail_executable(managesieve): /usr/local/libexec/dovecot/managesieve
mail_plugins(default): acl imap_acl fts fts_squat autocreate
mail_plugins(imap): acl imap_acl fts fts_squat autocreate
mail_plugins(managesieve):
mail_plugin_dir(default): /usr/local/lib/dovecot/imap
mail_plugin_dir(imap): /usr/local/lib/dovecot/imap
mail_plugin_dir(managesieve): /usr/local/lib/dovecot/managesieve
imap_client_workarounds(default): delay-newmail netscape-eoh 
tb-extra-mailbox-sep
imap_client_workarounds(imap): delay-newmail netscape-eoh 
tb-extra-mailbox-sep
imap_client_workarounds(managesieve):
dict_db_config: /usr/local/etc/dovecot-db.conf
namespace:
   type: private
   separator: /
   inbox: yes
   list: yes
   subscriptions: yes
lda:
   postmaster_address: postmaster at xxx.xxx
   mail_plugins: sieve acl
   mail_plugin_dir: /usr/local/lib/dovecot/lda
   deliver_log_format: msgid=%m: %$
   sendmail_path: /usr/sbin/sendmail
auth default:
   mechanisms: plain login cram-md5
   username_format: %Lu
   passdb:
     driver: sql
     args: /usr/local/etc/dovecot-sql.conf
   userdb:
     driver: sql
     args: /usr/local/etc/dovecot-sql.conf
   socket:
     type: listen
     client:
       path: /var/spool/postfix/private/auth
       mode: 432
       user: postfix
       group: postfix
     master:
       path: /var/run/dovecot/auth-master
       mode: 384
       user: vmail
       group: vmail
plugin:
   acl: vfile:/usr/local/etc/dovecot/acls:cache_secs=300
   acl_shared_dict: file:/var/db/dovecot/shared-mailboxes.db
   convert_mail: maildir:/var/spool/vmail/%d/%n
   expire_dict: proxy::expire
   expire: Trash 365
   sieve: /var/spool/vmail/%d/%n/dovecot.sieve
   sieve_dir: /var/spool/vmail/%d/%n/sieve
   sieve_global_dir: /usr/local/etc/dovecot/sieve
   fts: squat
   fts_squat: partial=4 full=10
   autocreate: Trash
   autocreate2: Drafts
   autocreate3: Spam
   autocreate4: Sent
   autosubscribe: Trash
   autosubscribe2: Drafts
   autosubscribe3: Spam
   autosubscribe4: Sent
dict:
   expire: db:/var/db/dovecot/expire.db