We picked Omar's place because we wanted somewhere close to St Pancras station so we wouldn't have to walk too far to catch the eurostar. I don't think you'll find anything closer than Omar's!
We found it very convenient- we had time to take photos at platform 9 3/4 at King's cross (for Harry Potter fans) but also stroll around the canals to look at the narrow boats.
Omar was very understanding when our flight was delayed by a few hours and ensured someone was still available to meet us for check in.
Given how close it is to the train station, it would be a handy place to stay if you wanted to catch the tube to get around London.
The only thing that was not perfect was that the room was quite not due to a heatwave- however I think that this was abnormal weather and usually this wouldn't be a problem.