I hunted with one of these for the first two weekends of the 06' season. I had the new style like the one pictured above as well. After the second weekend I tore it off and replaced with a biscuit.

The plastic rest thingie broke on me after a few hundred shots through the bow, this happened on the first weekend of the season. I had to install the replacement plastic post and check the sights by way of car headlights at night before the next morningshunt. The second weekend of season after replacing this plastic thing, I had one of the largest does I've ever seen run into one of my shooting lanes and stop at 20 yards (bumped by a neighbor). I grabbed for the bow off the bow hanger and didn't realize it in the rush but must have bumped a limb with my arrow knocking it off the rest and down into the metal bracket part of the rest. I didn't realize this happened and hit full draw and somehow luckily completely missed her at only 20 yards, only reason I know it happened is because 2x of the fletchings came off the arrow and I could see the marks on the moleskin I put there from where the arrow passed across. The lack of total containment fell short for me here and I just couldn't see the benefits.

This is why I still to this day only use the biscuit for hunting. With everyones unproven theories about why the biscuit shouldn't shoot well, I've never seen any difference in my shooting from a biscuit to any other rest I've used for hunting. It's simple, cheap, and effective. Just MHO.