It fits in beautifully. The rectangular tabs in Megs hands tab in perfectly with the shotgun. Basically adds to the badassery. Optimus looks terrible with it tho, so ya give him the FOC gun, it looks better. If you can find him, get hound for sure. He's just one of the best so far. Leader Grimlock is actually really good, but underrated. Picked him up for $30 on sale, totally worth it. Leader Optimus too, but meh, it was ok...fun to mess around with but ya. Strafe was incredible so ya.
I got him recently. I thought it would be terrible considering the paint details on the Hasbro version, but he's just amazing. The articulation is better than any prime we've gotten so far, and the shotgun looks great, especially if u have dotm megatron. definitely a must have from this line, at least imo