I just bought one for my mare last Friday! I LOVE it! I've tried corner buckets, normal buckets, and feed bags. My mare will fling all of her feed out of the corner buckets and it off the ground, sand included. With the normal buckets she'd take huge mouth fulls and let it drop to the ground eating it that way. The feed bags worked the best but she'd tear them up really quick, and I just couldn't keep buying/ordering them. Even then I was worried that she would be eating too much at one time and I just couldn't tell. So I bought her the Pre-vent feeder. It is amazing! All of her eating habbits have stopped because her feed fits into the holes, preventing her from flinging it all to the ground. The holes are shapped so that she can't fit her hole mouth into it, making her nibble from the top and then licking when she gets to the bottom of the hole. Because of how wide the bucket is she feels comfortable and keeps her head down. I just love this bucket. I'm not sure how durable it is since i've only had it a week and I take out after each meal because my filly was putting her foot in it and kicking and pulling it (with her feet arg).
Awesome Miss Take- Storm- 15 yr APHA PHBA Mare
SS Catalena Doll- Claire- 2010 AQHA Filly