>>> Looking at Halfords site
Aaagh!! NO! NO! NO! A thousand times NO! Halfords are ruddy expensive! Try a local tyre-&-exhaust centre.
The much-maligned EU has imposed a really useful labelling system and, irrespective of where you're buying from (or the brands you're considering), it's those labels which you need to look at.
The most important one is the ability to stop quickly, particularly in wet conditions. Fuel economy will be important to many people as well though. If you're driving an old banger, road noise probably won't matter much to you but if you're driving an executive car you might regard it as important. The labels look like this and are self-explanatory:
http://tinyurl.com/k2vwcsz