like said in some earlier posts...there are some spots on the caliper that can be shaved no problem with the only(as if minimal) consequences being heat dissipation issues which could lead to over heating and brake fade sooner that otherwise wont compromise the integrity of the caliper. If too much is shaved from the face however, namely the area behind the pads, the caliper can be made to flex under the load of heavy braking which, when coupled with the regular heat of braking, can easily cause cracks in the metal. i wouldnt shave them under any circumstance.

 

hehe... you guys wouldn't even want to see what my TT calipers look like...

but... in defense... i have no problems whatsoever, hard braking and all

i completely shaved off the decorative part to the point that its pretty much flushed and maybe a few mm all around the upper edge.... all this PLUS an 8mm spacer to clear my stupid wheels

 

I've only modified cast/steel calipers; wouldn't do it on aluminum calipers.
I put BMW M1 calipers on my Fiero, had to slowly grind away to clear my Superlegerra type wheels.
Remind me not to get a Mazda.