I got them on my valver, didnt notice a difference but they can be relied on more. I changed them cause one of my original flexys failed an MOT. Dead easy to fit ASSUMING you can get all the unions to undo, they are famous for seizing, soak in WD40 a few times before hand, even the day before. Rear ones are more awkward to get spanners etc into, hope that helps
Ps take time with bleeding afterwards to make sure its spot on with no air, change all old fluid for new