Functions or aliases?

[alex <radsky@ncia.net>]

I've been using the following to access MS Win 98 from
Debian.

alias win+='mount -t vfat /dev/hda1 /mnt/hda1; cd /mnt/hda1; ls 
-aF --color=auto'    (This is located in   /root/.bashrc)

By simply typing 'win+' all of Win98 becomes accessible for 
copying, moving, or editing in either direction. I've even made 
a complete 4 GB backup of Win98  after executing 'win+' with 
this alias:

alias bup='cp -afv /mnt/hda1/* /mnt/hdb1/ '

(alias win-='cd; umount /mnt/hda1'  is used to unmount)

I've read that aliases should be limited to simpler
commands such as:
     alias cd..='cd ..'  or  alias lsl='ls -l'
and that aliases like my win+ should be structered as a function 
instead of an alias.  I've tried the same command in  function 
form and I don't see any difference.

So what's the reason why compound commands should be in function 
form?   I suspect that it might be because long commands tend to 
become word wrapped, they may not work but in function form, 
each line is short enough so word wrap doesn't occur.  I had 
difficulty with some longer aliases until I discovered that word 
wrap has to be turned off.

Is there some other reason to use functions instead of aliases 
for complex commands?