The WEKAF helmets are ideal for beginers as it offers more head protection, The next step is a modified helmet that the 'Dunnage Brothers' (Kris and Mike) have had made for them. It's called the Evolution helmet and looks like this:
It's a normal full contact head guard that has had bits added to it. The beauty of this is that if the fight goes to the ground the helmet stays on and it doesn't interfer with the flow of the fight. Also it's a lot lighter than the WEKAF helmet so the strikes to the head have more impact and therefore more incentive to protect the head.
The first clip in the 'Video Section' shows a fight using the 'Evolution' armour.
Hope this helps.