I have both the small and pro.
For small I can fit in:
EM5 (mount with20/1.7) and 25/1.4 in the centre slot created by padding, 7-14 plus 45/1.8 on one left slot and the FL600R flash (or 100-300 or 12-50 plus small flash from EM5) on the right slot. The 100-300 will be a bit tight after fitting in all the stuff. Note that I cannot afford to bring my full grip to this EM5 along. I can still squeeze in along without the vertical grip. Normally I will just bring the EM5 + 20/1.7 + 25/1.4 + 7-14 + 45/1.8 + 12-50 along with small, plus small flash.
For pro:
All of the above. Meaning EM5 + full grip + 7-14 + 20/1.7 + 25/1.4 + 45/1.8 + 12-50 + 100-300 + FL600R + small flash. FL600R will be placed in one of the 2 front pockets. Batteries, SD card and lens cleaning/blower stuff in the other. A bit heavy but can carry for short period. You might need an additional padding to cushion the 100-300 from the 45/1.8 (which I left it unmount from the EM5) on the right or left slots. Basically, it will fit in all you stuff in short and if you need an additional flash for yourself, you can still use the front pockets.