Well, as I said, I spent some money and got the Alpine string-things. The jury is still out. They don't seem to do quite as good a job as leeches, but they are still on the string and in one piece. I don't have them served in as I have a lot of twists in the string. They have a tendency to turn 90 degrees. That is, when you put them in they are more or less horizontal. They want to turn and face vertical. But they are still there and doesn't seem to matter. I chrono'd the bow and lost a whopping 3 fps, about the same as the leeches.
Also got the Alpine limb savers for split-limb. Now these are definitely different. No plastic grommets, no screws and no rubber glued to the plastic. Just a silicon thing that easily twists onto the limbs. My fear was that it would move around or slide on the limbs, but that hasn't been the case. I can't seem to be able to tell a difference between them and Simms, and at about $8 cheaper I think they are the better product. If I encounter any other data I'll post again.