Two of us stayed at Sumas appartment for two nights and it was a very pleasant stay. The host and der husband are very friendly and nice people, we felt welcome and got lots of hints on where to go and how to get to the places we wanted to go (like city center and the nearest beach). Yes, you have to walk a bit to the bus station, but from there the buses go very regularly into any direction and the way is really nice as you get to see the "real", non-touristic part of Heraklion. There are grocery and bakery shops not far from apartment as well as many places where you can get something to eat.
Suma picked us up from the bus station and took us to the airport on our departure date which we really appreciated.
As the apartment is close to the airport, you can hear the starting planes, but for our short stay it was not a problem. The price and the equipment, cleaningness and size of the apartment were perfect and it was a great starting point for city exploration and welcoming temporary home when coming back.
I definetely recommend Suma and this studio and will be glad to come again by my next visit of Heraklion.