Marcus is a very polite and friendly host, he helped with my luggage and tried to show me his city even if I didn't have much time to enjoy it.
The guest room is very well kept, clean and with a huge and comfortable bed; his place is located in a good position, not far from the station that can be easily reached on foot.
Personally, I never tried to stay in a private house during my travelling... and I'm also afraid of dogs! However, Eddy is a very well educated animal, I managed to pet him some times (very rare, from me!) and my experience with both of them was pleasant.
I highly recommend these hosts for a short trip in Bristol!