You should tear out a section of the roof ribbing - it looks too "perfect" for all the debris on the bottom.

Wow! Very convincing! Well done.

You might consider taking out some of the ceiling ribbing. to better match all the destruction and rubble. The roof is still too "perfect" looking.

Nice Blend Author.. Good Luck!

Good job; looks convincing (may be you could flip the background so it matches the direction of light on the church).

Good job, well blended (May be you can flip the background to match the lighting direction).

Well done, believable result. Nitpick would be that the background buildings get their light from the opposite compared to the foreground, but that would be a matter of flipping. The mess in front fits well, nice masking. Good luck!

Wow, good idea and lots of tedious work here, nice chopping (literally)!