Yup. Totally agree with you on the aspen. I'm a total clean freak, so aspen is out. Tried it and did not like it at all. once they go, you have to scoop out the main waste, and then go looking for more in the surrounding areas but of course all the liquid stuff seeps to the bottom, so you gotta disinfect the glass in the meantime you're getting all the surrounding aspen wet and it molds... ugh, I can go on and on about how much I hate that stuff.
The carpet seems like some effort too, but at least you're keeping the tank spotless. But I think I would need 4 pieces for my tank. I would go through 2 a week easy.