I have both but traded the .25 WC for another impact, here are the things I like about the impact over the WC:
1. Power adjustment that can be fine tuned to the range you need
2. valve adjustment, to adjust the tone, speed and air efficiency
3. larger mag capacity, almost double the WC
4. larger air supply, if your shooting 33g at 875fps you will get around 20-25 shots more over the WC at the same speed, but the WC has to be modified to shoot that high, the impact are all external adjustment to shoot that speed.
in .22 the impact can shoot over 160 shots per fill at 32fpe
5. will accept different air capacity air tube/bottle
6. shorter in length, WC just feels to long for a BP for me
7. external reg pressure adjustment, it will take you about 15 min on the WC, about 5 seconds on the impact.
8.impact just looks way cooler 2 me.
Now the WC:
Out shoot the impact out of the box, if you don't want to adjust anything and just shoot this BP is for you-----> that's ,,,,,said, it's a boring BP for a guy like me that love to adjust/fine tune AG. Just wish it had a 3 way power adjuster.