I had the very same battery fitted at a Halfords Autocentre a couple of months ago and it wasn't a good experience. First off, they fitted a different battery with a lesser rating and warranty instead of this one with the 5 year warranty. They didn't tell me they had done this, but I made a point of checking under the bonnet before leaving the premises and found out. When I complained about this, I also asked about coding the new battery to the car and found that they failed to do this, despite this being a part of their 'standard' installation service - probably because the lad who fitted it was new in the job and didn't know how. As I replacing a non-AGM battery with an AGM, I was keen to get this done to avoid any issues with battery charging.
They did eventually sort this out and gave me a discount on the job, but it didn't give me any confidence in their service capability.