Via Flickr:
Olympus OM-D EM-5 with the Panasonic 25mm F1.4 vs. Pentax K-01 with the 21mm F3.2. The Olympus is sitting on a lens hood because the EVF extends from the back of the camera. As you can see, this actually makes the Olympus deeper than the “big-boned” K-01. That would change of course if you swapped the 25mm/F1.4 for the more pancakey 20m/F1.7. On the other lens mount, the new XS40mm F2.8 would slim down the Pentax considerably too.
Olympus OM-D EM-5 with the Panasonic 25mm F1.4 vs. Pentax K-01 with the 21mm F3.2. The Olympus is sitting on a lens hood because the EVF extends from the back of the camera. As you can see, this actually makes the Olympus deeper than the “big-boned” K-01. That would change of course if you swapped the 25mm/F1.4 for the more pancakey 20m/F1.7. On the other lens mount, the new XS40mm F2.8 would slim down the Pentax considerably too.
At the end of the day, it’s a practical wash. The OM-D may be marginally smaller but not significantly so. So do you want weather sealing or a top notch APS-C sensor? Do you want an EVF and a tilt screen or clean ISO3200? Decisions decisions!