Ive had a number of Luminex boxes suffer from 'crashes' due to voltage drop on the internal power supply. I've had to replace a number of Node8's on shows, where they've just 'frozen', with Artistic Licence products
I can recommend the Artistic Licence Range of DMX/Artnet products:
Cata-Lynx
http://www.artisticlicence.com/index..._id=&order_id=
Ether-lynxII
http://www.artisticlicence.com/index..._id=&order_id=
Data-Lynx
http://www.artisticlicence.com/index..._id=&order_id=
Do contact me if you require further infotmation or pricing.
Simon