Plastic vs Metal Chastity Devices

A fortnight back, the spouse and I planned to stick with our word, skipping any cage experiments. I’d had some fairly lengthy periods on the honor system before. Then, I spent a weekend in an old CB-2000 that I purchased nearly ten years ago but barely used since acquiring it. Back when I bought the CB-2000, I was let down by how easily it could be pulled out. Security felt more critical to me then because my wife wasn’t particularly invested in the game yet. Now, though, ease of removal matters less; I assume the honor system motivates her enough not to try pulling it off herself. Plus, I found myself calmer this time around playing together and really “settled into” wearing it (especially by day two). It was a surprise that I could wear it overnight for two 12-hour stretches without issue. That said, the CB-2000 feels quite rough compared to devices in the next tier. How much better is the CB-6000 for those who know? The photos suggest improvements have been made. The Watchful Mistress appears to share the same concept but uses metal and costs a bit more. One potential downside would be ensuring I ordered the correct size since it comes with additional rings. Perhaps I could estimate based on the ring of my current CB-2000. What are the benefits of steel? Airport security isn’t really a concern for me. I want to avoid anything requiring a piercing. Any thoughts?