So answer me this......why did ford fit a 25mm master cylinder to the S2 if the 23mm does an equally good job...............

Clearly your knowledge is better than the millions of pounds a car manufacturer pours into developing a car

Anyway......bullsrs, its up to you what you do but hopefully you can make up your own mind which is the better option. Feel free to give a PM or whatever if you get stuck or want any help