This is my own darn mistake, but....

I broke the mounting ear on my front XT caliper. So I found one on-line, ordered it and when it showed up I noticed it was painted silver. After some research I found it was a ROAD caliper. Heck, I didn't even know that Shimano had gone into full production on the road version.
After looking it over, I decided it just looked like a painted XT caliper so I installed it.
Now I'm wondering if I made a mistake.
The front modulation is weak. Much weaker than the rear or the front one it replaced.
Does anyone know if there is a structural difference between the two?
Before I go ahead and replace it....
Any help would be appreciated.