I just got 3 of the 300 Watt heaters back a little while ago so we will see if they are worth it it not. They look well built but I do really like the fluval pro heaters I have but they just don't put out the power these do.
OP, did you calibrate your heaters?
I'm not a fanboy, but while you've had experienced only one used ecco line filter, you bash the whole eheim product lines, "...I've had it with their products. Everyone speaks so highly of them, but all my experience with them has been one disappointment after another..." I don't think that's fair. Impeller doesn't last forever you know although my classics seem to last very long time.
4 out of my 5 eheim classic's were bought used because I trust their motors and like the overall simple design, and they're still running like a champ for 3 years+ with no replacement part yet.
Had bad experience with all three of the eheim filters I owned a couple pro series and one classic. So I'll never spend the outragous amount for one of there big filters. Hard to beat the value for the dollar with an FX5