did you ever get to demo the radiance? i am debating martin vs. lemaitre as well. i work at a 650 capacity venue with 35 foot ceilings. seems like a similar scenario to yours.
The Radiance is much better than thhe Neutron, IMO. Runs better, less maintenance, better design, etc. I don't think they're in the same league at all. Never used a Martin atmospheric so I can't comment on them.
actually the radiance was a completely new design from the north american lemaitre team and the neutron was not. The Radiance is 100% better than the neutron about the same money. seperate fan and haze DMX channels, low consumption, high output - I highly recommend the Radiance, you can't go wrong!