"consistently run away from an RMX250 at high speed" LMAO....I highly doubt it.
The WR200 is a great bike. It's an 89-92 YZ 125 converted for woods. Just like a 200EXC, but much older tech. Electric power valve which was pretty impressive for 92. Basically a 125 with some balls. It doesn't have the torque the KIPS gives a KDX, but it will rip up top! Suspension needs reworked as it's stock YZ spung/vavled--unless you're gonig to MX it. If reworked, it's a better susp then a reworked 89-94 KDX. I love them, but the lack of time they were imported makes them a fairly bad choice to own in the states anymore. I know they made them outside for a long time, and it sounds like parts aren't a problem where you're at.
On the other hand, you'd have to shoot me to get my WR250. People spend a ton converting jap MX bikes for woods and still don't end up with a wide ratio trans. The RMX, and WR are the only jap 250's you'll ever find this on! The WR does make a ton of power(the strongest YZ era to date), but you just need good throttle control. Some things I've done to make the WR a little better are:
Install YZ seat/Tank - if you need high capacity then you must find a 93-95 YZ high capacity tank to match the YZ seat. This will slim the beastly wide tank down which is this bikes greatest downfall(although it's only about 1/2" wider than a 89-94 KDX).
I still run stock the flywheel on mine(which feels like a 10oz on a YZ), but a few more ounces couldn't hurt.
I run a KDX 35mm PWK carb. A 36 will fit the boots a little better, I just had this carb laying around and tried it one day. Drastic rejetting required, but I'll get you close if needed. This was a great improvement. Adds to the bottom, and helps the hard midrange transition. Loses a hair on top, but this engine has some to lose! This thing is a tractor. Torque even the ingenious KIPS 200 is envious of. I climb hills a gear(or two) high off the pipe 1/4 throttle and leave lots of other 2-strokers baffled-heck, it baffled me for a while!
Rework the susp!!! MX stiff and a woods nightmare in stock form. Exact opposite of the stock KDX issues.
Obviously I vote for keeping the WR. I was slower on my WR than the KDX when I first got it, but that didn't take long--Now I'm stopped at the trail head with my helmet off having a smoke when riding with my fellow KDX'ers. It is a little more tiring to ride, but only when comparing WFO to WFO. The bike also made me faster when back on the KDX as it feels like an oversized 80.
All three discussed are great bikes! I still love my KDX even though it's setup for my 110lb girlfriend, and like the newer gen better. They are truely the Honda XR of 2-strokes. Hope my ramblings are usefull....