We are a family of 4 and really enjoyed our stay for a week in the Northern Quarter. The location is great with lots of restaurants, bars, museums & galleries within a 10 minute walk, or you can make the short walk to the tram stops and venture further afield.
The actual apartment is spacious & light and is a nice place to relax in the evening, there's a large dining table if you want to cook or have a delivery.
Being in the City centre it is busy with people outside and in the local bars but we didn't find it intrusive at all. The only issue with noise that we did have was the glass collection from the local bars which occurred most mornings.
We'd definitely recommend Matt & Steph's apartment if are looking for a City break in the UK.