First of all, Sasha was a wonderful host--very kind and flexible.
As for the flat, it was everything I needed. Among all of the positives of my stay: a private room with very protective blinds, bathroom, bath towel, great host, and washer for my clothes.
The negatives: the wifi was spotty (Sasha said this was not normal and that he will be having it fixed), it was a 30 min bus ride from the HB (the price reflects this), no A/C (this is normal for CH), there is a big hill from the bus stop to the flat (this shouldn't be a problem for most people).
In sum, I would highly recommend staying with Sasha (and Tina). Their flat is a tremendous value for Zurich, and the negatives listed above are minor and outweighed by the positives of the experience. I would definitely stay there again.
Thanks again Sasha!