Haha, That's where I bought my Cascade from(The really tough looking guy that always helps me got my business!)! Just because he was filtering ALL his tanks with Cascades, that's product confidence!
I like that place, but he's kinda expensive on hardware/accessories. I usually get my fish there or Midway.
I am running a RENA composite heater (200W)ATM, I moved it and the filter I attached it too (Magnum HOT250) to this tank last night, but it has a 5* tolerance, if it is hotter or cooler than the set temp it flashes, and apparently doesn't heat when flashing! Stupid... I adjusted it this morning, so I am hoping to at least be at 75* when I get home... The Rena is basically a inlet screen with a heater built into it, jut attach your filters inlet into the top and your filter will circulate the heated water, just a variation on the same theme...
I'll look into the Hydor ETH though, looks like it works the same way, but hidden better.