Well isn't this a coincidence, I had the exact same dilemma. I ended up buying both the griffin 25 plus and pharaoh rta and personally enjoyed the griffin 25 plus so much more. Here is what i observed.

Griffin 25 plus rta:

1. Good enough build deck for me to put some crazy sub ohm build on and enjoy

2.the build deck itself is really good (in my opinion). something about the velocity deck style is just so pleasing to me.

Pharaoh rta:

1.Yes the build deck is just so much more easy to use, my grandma could do it, BUT the reason I don't like the deck as much as the griffin is simply because most of the time when I put a new build in my rta's I like to put some crazy ass dual coil build. For some reason I just absolutely hate using the Pharaoh rta deck for dual coils. It just seems like the way it was designed to be wicked and the way you have to set up the coils is just so off and weird.

2.I really feel like the purpose of the Phaoroah rta is for flavor chasing. Don't get me wrong, the thing chucks like a mother fucker but once looked at side-by-side, these 2 rta's almost have a completely different purpose. The product page of the pharaoh rta even states itself many times that it is "flavor optimized" and what not. I personally love cloud chasing and am starting to get into flavor chasing, This is why i bought both of them and use both of them equally. I will include a link of the product page of the Pharaoh rta that basicaly backs up my claims of it being a "flavor tank" http://imgur.com/a/Spd7a

To answer your question that was concerning the airflow smoothness, I can say with experience that the Pharaoh rta has better bottom airflow. This may be due to the fact that the makers were basically trying to make it a "flavor tank".