Congratulations on your new Air Lift Performance kit, you are going to love it!
When I did my winter install last year it seemed like everyone was talking about adding a second compressor so I added one before actually using the system. Therefore, I cannot comment on the performance of a 2.5 gallon tank with one VIAIR 380C compressor. I am very happy with the dual compressor configuration I have. One has to assume dual compressors would functioning approximately half the time of a single compressor. Also I am very happy with the trunk tire well install since with the carpet back down you will never visually know the system is there.
My recommendation to you is go with a single compressor to see how you like it but make sure you configure your layout to accommodate a second compressor in future. Other than the layout the only additional issue would be supplying the power feed directly from the battery to the second compressor. You may want to consider running a second set of 10 gauge power and ground wires when you do your initial install to save time (assuming your battery is in the OEM location and not relocated to the trunk) if you decide to add a second compressor later.
In terms of compressor comparison your 444C is a little more powerful than a 380C:
380C – 200 PSI / 1.34 CFM
444C – 200 PSI / 1.76 CFM
Tire well layout – polished 2.5 gallon tank, two 380C compressors, three SMC ¼” water traps, manifold, and dual wiring harness.
Carpet down.
Since I was recovering from hip replacement surgery when I did my install I spent more time taking pictures than actually working on the car. There is a great deal of information in my install thread.