QNX 4 as a file server

I have a Novell server at the office that no one really understands.
Currently it is used to serve up files/applications to Windows machines and
to provide network printing. Does anyone have any experience using Samba
and QNX as a file server? Is it likely to work as well ( fast) as the
Novell software? We have about 25 computers making use of the Novell server
currently. Could Samba handle this assuming we had a fast CPU with lots of
memory, good disk sub system and 100 Mbit Ethernet? Also what level of
permissions/security can the Samba software provide?