Bristol- Marriott v Airbnb

[Minniemountain]

DH and I are planning an anniversary trip to Bristol.
We were going to stay at the Marriott on College Green but now I've found a flat on Airbnb near Millennium Square.
DH thinks the flat idea is a bit "studenty", I'm wondering if the Marriott is worth the extra £50 (1/3) per night for a pool and a slightly nicer location.
Has anyone stayed at the Marriott?

How are you travelling there? If you are driving then the Marriot has a car park and parking spaces in that area are rare (and expensive).