Product review (5 stars): Good ice maker, well worth the $$
I give this Knox Portable Ice Maker a big thumbs up.  Dead simple to setup...since this was new out of the box, and has that new "Made in China" smell...I followed the directions to use 1:1 solution of vinegar and water at first.  There is a cleaning function for the ice maker, that will basically flush the system through 5 cycles. (not making ice)  You then empty it out from the little drain plug in the back.(great feature)  I ran two more cycles with clean water to flush the vinegar out and started making ice.  I chose the small size at first, and it took about 10 minutes.  They are cute "baby" ice, great for crunching on, but not so great for drinks. I then switched to the large size and it took about 8-9 minutes for each batch.  Once you get a couple of loads in the ice tray, the cubes stay pretty cold, but only because of the other ice that is in there.  The ice on the bottom of the pile will melt back into the reservoir.  As others has said...the ice is "wet", so when you transfer it to your freezer, it will freeze and stick together.  I put the ice in a ziplock bag, freeze it a while, then break it up in the bag to transfer to an ice bin.  I ran it just about all day, with a full filling of water, and then only filled it halfway and ended up with lots of ice, since it goes non-stop until the bin is full, or it beeps and lets you know it is low, or out of water.  This one also has a digital timer function, so you can set it up to make ice at your designated time.
Is it quiet?  Well...that depends.  The "beep" is super loud.  The compressor is not loud, but runs constantly with the fans going, while making ice.  The loudest part is when it dumps the ice.  I didn't find it annoying at all, but if you were in a very quiet space - you would definitely hear it. I would say it is as loud as desk fan on medium - not annoying, but still there.  It is like a mini air conditioner after all.  Size?  I would say...half the size of a microwave oven, but taller.