So when it comes to your average 870 Express with the normal cap, we know there are dimples that have to be removed for the extension to work. What does Remington do with the 870 Express defensive models that come with the factory extended magazine tube? Do these models use the Express magazine tube with the dimples removed or do they use a Wingmaster or Police tube that doesn't have the dimples in the first place? If I got one of these models and wanted to use a magazine cap without the extension, would there be problems with the cap wanting to turn loose with recoil or do they use a different retention system than the Express models?