Original bird locked is a good silicone device. Do not get the Neo though one size fits all,is rarely a good idea. Be aware that with silicone You will be able to escape if you want. Also know that you will need to keep things lubricated to avoid the gripping that happens from silicone. I have the original bird locked and I like it. I had the neo and it was a complete waste of money. I would like to add that what slave d said and agree that the holy trainer is hard as wood when at body temp. If you would like to purchase a holy trainer flip over to the marketplace. I have just posted an add.
Good luck!