All good points but...
1. Only a few of my smaller animals seem to burrow in it but for them it is probably a benefit. Based on my observations of their behavior, I really don't think the larger ones care. They also wind up on things and in places and positions that indicate they don't seem to care about having a soft surface, cushy surface.
2. The apsen itself might not have dust but my snake room is also a living space and is quite small so there tends to be a "dander" which sometimes gives me a very slight reaction. It is likely from mold or fecal residue in less than fresh bedding, fresh is a relative term here as after the first defecation it is one its way to funky. I fairly fastidious about spot cleaning but it's never perfect and unless you change bedding on a frequent and rigd schedule...
3. Just now trying it but my thoughts are that it will be very simple to swap out the paper, wipe the floor and put it back together all clean and dandy. That operation is a lot more involved and messy with aspen. I am definetly concerned though about them becoming more exposed to fresh feces.
This guy spent the night and most of the morning like this...

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