Wiki examples use eth0 and eth1 for bonding is there a downside to using 3 nics?

[cam_cb]

Hi

As per the subject, I have read http://pve.proxmox.com/wiki/Open_vSwitch and I see the examples point to using 2 nics for bonding, is there a downside or diminishing return if I bond with 3 nics or any known gottchas? - is there a linear return in performance? also during testing, what should I look for - high CPU in Proxmox? maybe exhusted cpu in the physical switch?

Thanks in advance

Cam