Black class doesn´t mean, it is Military personal only. It´s just a goup of Benchmade products.
I would recommend the 520 Presidio over the Monochrome for the better handle the Presidio has.
I would rate the Griptilian over the Presidio for overall properies it has (the 550 without HG or 551) price and weight are lower, steel, fit and finish are equal. Scales material and partial steel liners are often questioned. For me, they are two aspects, why the Griptilian is such a great knife.
I had the automatic version of the Presidio since 2003 and the manual 520 maybe half year later.
I loved to carry them over years. The manual was replaced by Benchmade on warranty because of a problem with a disengaging lock during a spine whack test and i got a custom blade for my model. Since i switched to a little fixed last year, i have carried a 520.
After all the newer models i have seen, i found quality has raised up. I found the aluminium scales, offered now much grippier and tougher than before and the lock engaging much better than earlier..
Even though, the Presidio is heavier and even though there are good reasons, why the Griptilian is the better value, i prefered the Presidio over it.
If money is not in question: Presidio! Otherwise: Griptilian 551
At the moment i am happy with a much smaller HK 14210.