I'm running 1.2b8 and would like to enable polling and link0.

Question-1: Are the shellcmd below correct and if so where in my config file 
do they belong?

<shellcmd>sysctl kern.polling.enable=1</shellcmd>
<shellcmd>ifconfig fxp0 link0</shellcmd>
<shellcmd>ifconfig fxp1 link0</shellcmd>
<shellcmd>ifconfig fxp2 link0</shellcmd>

Question-2: Any downside to using polling and link0?

Thanks in advance, Roy...