What chutes are you guys using. I have priced a Big Valley M1-V, Preifert S04 and a Powder River XL. All with automatic headgates. What is your experiences with any of the these models. I noticed the Preifert has a 'scisscors' type headgate. Do they work nice? I'm just looking for any advice on durability and operation. I will run 350 cows, the calves and some bulls through this device. I will also use it for AI and palpation work. Thanks for any info.