Did you ever use DAT? DAT uses PCM digital encoding, just like the A10 (and I assume all solid state recorders), so it shouldn't have any inherent hiss like a cassette tape does when you turn it up high in quiet passages. The only way I can even think of that it could be different (if working properly) is that it would be possible to have recorded a tiny bit of noise from the recorder mechanism, but really I can't imagine that happening. A DAT deck could have a problem with the input or output jacks, or they could be made cheaply, possibly resulting in noise, but that could also happen in a SS recorder. I recorded with DAT for 10 years and don't remember ever hearing any hiss, even when playing very quiet passages at high volume.
Anyway though, I really like using the A10 for the most part - mostly because it's so small, and being able to control with your phone is so nice. But i think it's rather cheaply made as far as material quality and possibly internal mechanisms as well. After about a year and a half of use, the bluetooth on my unit completely stopped working, so I had to learn how to use it with the tiny buttons and tiny screen. Then after another 6 months or so the buttons started acting up; sometimes I would have to press record several times to get it to start, and same thing with adjusting the levels. It got gradually worse until it was nearly unusable, so I bought a new one about a month ago.
Of course, my unit got VERY heavy use, as I go to about 200 shows per year. The bluetooth problem could have been a fluke, but I really don't think that the buttons should stop working properly even after using them for nearly 100 concerts. I think at some point my old unit had stopped turning on the red light when recording, because when I started on the new one I was surprised to see it lit. I remember nulldogmas had a problem with his where the display screen stopped working, though I think it eventually started working again. And someone else had some kind of issue where using it with a certain battery box caused one of the channels to stop working, which is just bizarre.
My new one is a tough to actually connect to my computer, because the USB slider usually doesn't lock in place, making me have to awkwardly hold the slider very tightly to plug it in. I thought about returning it for that, but nulldogmas told me that his unit never locked in place and he didn't think that was an intended feature. I really think it is supposed to lock and he got a unit that was slightly defective. I decided it would be too much trouble to return mine though, and I didn't want to have to go back to using my old Tascam without bluetooth for weeks while it got sorted out.
Anyway, for anyone considering getting an A10, I definitely recommend it for ease of use, stealthability, and (internal rechargeable) battery life. It works great until something breaks, but IMO much more likely to happen than it should be. I also think it has a design flaw in that the control lock is on the same switch as the power, which once caused me to accidentally turn off my recorder and miss a minute before I could get it recording again. Of course that wouldn't have been an issue if I had been using the bluetooth.