Velocity T4 or Mak 4?

[newgeek]

Hello everyone,
I would like to call on your experiences. I am upgrading my return pump and have narrowed it down to the Velocity T4 or Mak 4. I can’t seem to find anything about the velocity being a pressure pump. I intend to run this through a SCWD and am concerned the velocity will not run as efficiently as it should. I would think from what I have read the Mak 4 should perform well under these conditions. Thanks for the input.
Have a great day,
Kelly