Attachment is a multi-valued field (MVF), so it does impose some additional
restrictions on your database (e.g. some queries won't work, some code that
doesn't test for fields that contains fields won't work, won't upsize, ...)
However, OLE fields prior to 2007 were incredibly inefficient in storage, so
not really useful anyway.
A third alternative is to use a text field to store the fully qualified file
name (including path and extension). This avoids the MVF issues, and the
bloat issues. You can then FollowHyperlink to view the file. Or, if these
are images, you can display it by setting the Control Source of an Image
control to this text field (new in A2007.)