We had a great stay at the Main Square Penthouse! Everything was as pictured on Airbnb - but twice the size! Excellent value for money. Great spot to stay in due to be central etc, it can be a bit noisy at night (in Porto people seem to party ALL night) but with the use of ear plugs we overcame that. Also we were especially grateful to be able to drop off bags off when we arrived, then go and have lunch and do a bit of shopping and then come back and check in.
We would definitely recommend and would certainly stay again.