How's the actual sound quality compared to a name brand?
I didn't bother replacing the stock head unit with a name brand head unit before installing this Android head unit so have no basis for that comparison, but most modern head units employ commodity op-amp components and produce equivalent output. Anyone serious about sound quality (to the extent that it even makes sense in a vehicle) will use the line level outputs to feed an external amplifier driving better speakers. The Android head unit in my Corvette feeds the stock Bose amp, which presumably is the appropriate configuration for this Android head unit in a RAV4 with the optional JBL audio package.
Can you run the GPS and make a BlueTooth phone call at the same time?
Yes, I can use iGo for GPS navigation, Torque to monitor OBD-II via a BT ELM327 device, and place a BT phone call simultaneously, which is true for the older Android head unit in my Corvette as well.
Can you adjust the MID in the sound settings? Mine is just for show and does nothing.
Yes, which is true for the older Android head unit in my Corvette as well. With your head unit, perhaps the bass and treble can be adjusted to achieve the desired midrange level (boost both to reduce relative midrange, attenuate both to increase relative midrange).
The 2GB RAM/32GB ROM version shows as US$311. Is this what you got?
No, I opted for the model with 2GB RAM / 16 GB ROM and will spend $10 to add a 32 GB MicroSD card if more storage is needed. The Android head unit in my Corvette has only 1 GB RAM / 8 GB ROM yet the 32 GB MicroSD card still has 26 GB free (primarily apps, music and Torque logs).
All these China units come with outdated maps. I have wince 6.0 version and mine came with IGO 8 and my maps were 3 years old. I just updated to IGO Primo 2.4 with text to speech and latest maps. You can find latest IGO maps by searching GOOGLE " USA & Canada HERE 2016.Q3".
What head unit is
not from China?

The Android head unit that I installed in my Corvette back in 2014 came with 2012Q4 maps (i.e.- just over one year old), and the late 2016 model that I just installed in my RAV4 came with 2011Q2 maps (five years old), which admittedly seems odd. The GPS Power forum is a good source for free
iGo map updates, and the latest is 2016Q3 as you pointed out.