instronics, what kind of security issues? I guess it could open up a bunch of ports and perhaps share my entire hardrive to the world if set up inproperly, but can't you configure it to deny all connections from outside the network?
Well, the security itsn't too bad to setup on it. You can restrict it to your local LAN and anyone who wants to access is going to need a user id and password. I would recommend using the same user names and passwords on the m$ boxes and on the linux box. That way when they want to access a shared drive, they only have to enter their password once... when they login to the m$ box. You can restrict it to certain IPs or certain computer names if you want. I have a huge book called Samba Unleashed... it is a lot of reading, but great for reference. I think I picked it up for about US$20 at a book outlet.

Unless someone breaks into a box on your network... samba is pretty safe IMO.
Do you open up your network to the outside? IE: are you running a server of any kind that people access from the web? If no, then I wouldn't worry too much. It is easy to understand and easy to configure. You can setup the security on a per user basis and use it as your print server too.

All in all, I love it. I would use linux/samba as my file/print server over m$ anyday, if the choice is mine.