Has anyone used or had good results using an inline heater like the ones that Hydor makes ?
http://www.hydor.it/uploads/immagini/gallerie/bf5f633e676af8128fcccdaf1390d213.jpg



I'd be interested in finding out how their lifetime/useage/efficiency compare to traditional submerged heaters (titanium or glass)



I've got to purchase approximately 300w of heating for my 90 gallon reef build (which will have 500w of MH lamps running 12 hrs/day) and I like the idea of running one of these heaters on my return line to the tank (and keeping the sump/refugium free of heaters)

any takes?