Absolutely loved staying here. Very convenient location close to downtown Austin. The place has window units to cool the place down, they are more than enough to keep things cool. Place is super clean and cozy.
As others have stated it is right near the highway but was still pretty quiet. Less quiet in the bathroom than the bedroom for some reason, but you won't be sleeping in the bathroom and the bedroom was silent (even with the bathroom door open). There is also a train track nearby, but I only heard a train honk once during the day and not at night. So I wouldn't worry about it being so close to the highway, it is quiet.
Loved staying here and would definitely stay here again when back in Austin. I completely understand why this place is often booked, it really is a great place to stay.