I think that your choices are all pretty good, but I definitely think the 0801 has some inflated prices right now, and unfortunately they don't look like they'll go down. Personally, I think the Umunmzaan is a very good choice, and the Strider is good, but not as much value for the money.
If I were to suggest something besides what you mentioned, I would say look into a Sebenza 21 or 25, like Ken44 said, they're amazing knives and will last a lifetime. If you aren't looking for anything right this moment, then you should also look around here on the forums for a Dskin Fire. You can get them for about the price you're in, and they're awesome knives. Elmax treated properly, dual-action mechanism with a concealed auto release, and stellar materials. On the downside, they're hard to find, and tend to reach above their starting price of $500, though not by too much.
I will say that the DGG, in my experience, is not my favorite way to get any Strider. It absolutely destroys pants, even heavy jeans, and it can chew your hand pretty hard when really being used.
Other than that, I think that whatever you choose, as long as you use it without sticker shock, you'll be happy
