kern secure level help

[Sean Murphy]

I have read different views about implementing a secure level on FreeBSD 
on the web

one said to implement it and gave certain things that it does at the 
different levels -1, 0, 1, 2
one said that it would break certain applications as the need to write 
to some /dev areas
one even said  it is a false sense of security

I guess by default FeeBSD runs at -1

what would most of you recommend doing?  is this primary to keep local 
users (ssh) in check? does it help in remote attacks (buffer overflow) 
is it even needed?