I was looking at the Dynamic case also when i was thinking of my upgrade to the open loop cooling. It is smaller on the top and the bottom which affects how much space you have to install the rads and work with internally. I went with ordering the O11XL instead to allow me more room to work with and the larger rads. The addition of fans on the bottom should really help with adding cooler air from the bottom of the PC up into the case which should help reduce temps and heat soak.
The only thing left is that I am thinking of adding a third rad to my system. I already have two EK Classic PE 360mm rads which I intended to use on the top and side while having 3 fans on the bottom pulling air into the case. The side rad fans I was going to set as intake and the top rad fans to exhaust. But now I thinking of getting a third rad which would be the EK SE 3600mm rad for the side which I would like to set up in push/pull intake and move the PE rad to the bottom with the fans set up to intake. I always planned on having the rear case fan set to exhaust from the start, but I have to take the time to measure up the space I have behind the side mount to see if it would fit the SE rad along with the unifan and still allow the rear panel to be installed without mods.
The XL case is just so much larger that it allows easier access and more room to work with. It's sitting on my shelf along with all my parts just waiting on the water cooled GPU so I can work on putting it all together.