This is absolutely true in some cases. With bows that have 'parallel' limbs, it's probably best to steer clear of dropaways that use the cable slide to raise/lower the rest. The reason being that bows with this configuration have very little movement of the cable slide and getting the rest to drop when you want is tricky at best. Not that it can't be done, but it usually takes work. Personally, I like dropaways that use the cable slide because the force of pulling up the rest is more evenly distributed to both ends of the bow and you don't have to take off the pull cord if you need to put some twists in a cable.