I grew birds nest in both high (400-600) and low (100-200) PAR, and they do well in both as long as the light distribution is good enough to penetrate between their tiny branches.
I actually tried to use low PAR as a tool to slow down its rapid growth and still found myself breaking apart colonies every 2 to 3 months, so high par isn't a hard requirement for their health.
But I agree about the flow - they love it, and its necessary to be able to keep them healthy.
When they grow to large colonies (20--30 cm) the internal branches may not get enough flow and start to die off, which for me is a sign that it needs to be broken apart and restarted.
From my own experience, it is a great SPS to start with, maybe after Pocelophora and Stylophora.