I bought 2 $3(yes three) ones off eBay, I was going to set them up to have each one feed once a day, but set one up for a test and it hasn't failed since. I'm using the small pellets, this thing has fed twice a day for almost a year now, only fails when I don't look at it for awhile and it goes empty. Original battery's too.. they came with it.
Anyways, all these fancy features and stuff tend to be what break on the pricey ones, and battery life, etc. So far, I'll put out a +1 on the cheapy's,.
Looks like the price went up to $9.99, might be able to find more, but this is the model I'm using.
http://www.ebay.com/itm/Auto-Automat...ht_4078wt_1270