You might look into the Wildview 3.0.
They are relatively cheap at $150 for a two pack and they come with two 2 gig cards. I buy rechargable "C" batteries at about $10 for two. You will need 4 per camera plus a charger for about $20 So for about $200 total you will have two cameras that take good daytime videos and pictures and ok night vids/pics with IR.
But if you really want battery life than I suggest the Bushnells.