All four knives you mention have sound reputations.
The Chinook, however, may be too heavy for some daily carries. I've also heard in one test too, on a post here a ways back, that the blade developed noticable play with a relatively minor exercise. Everything else I heard has been good.
The Wegner, not one bad thing I've heard on this unit.
BM710, I own. Excellent all around knife, especially in M2 steel. BMs aren't for everyone, since there is a good chance you'll have to return it for some minor F&F issue,l and wait all over again. On mine, as everyone knows by now a thousand times over, the blade is not quite evenly aligned when closed. The problem appears minor, and is probably more common than we realize, even in other makes. Besides this, the knife is outstanding. It aint pretty, and you won't go WOW when you take it out of the box, but it is a USER, and will probably outlast most others.
I also have the SERE 2000. A few have complained of theirs not passing the spine whack test. This happens with most brands of liner lock on a new model, that you will get a lemon now and then. Let me tell you this: this knife ROCKS. Built like a bank vault, with perfect fit and finish. When you heft it out of the box, you won't believe you paid only $120 for it. $15 cheaper than my 710. The lock-up on my specimen is truly impressive, better than anything I've felt. It's an awesome 1-2 punch procedure: flick your wrist with the blade slightly opened, and the loudest "clack" (same with Wegner) tells you this thing is LOCKED. It now feels like a fixed blade as you try to wobble it. I hammered mine with some spine whacks, and not a budge. If you order this knife, and you get a good one, which I'm sure you will, you won't want to buy another knife for a while. I get the strong impression Al Mar made a great effort in addressing some early complaints. Mine, by the way, has the "SERE 2000" stamped on the blade, so I know it is a newer one.