I agree with you about how good it looks in the tank.
I collected some off the beach (at the water's edge) last spring and put it in my 16g holding tank. It's a slow grower so it may reduce nitrates and phosphates, but certainly not as fast as some other macro algae that we commonly use in a refugium. It doesn't appear to want to attach to anything which I think is a plus! It also didn't do well (actually died back and turned white) near the surface of the water. I don't know if that's do to being too close to the air or, more likely IMHO, too much bright light from my leds. It's east to trim back as I can completely pull it out of the tank and trim it with a pair of scissors at the kitchen sink (so small bits of it don't get loose in the tank).