Need the extra little attachment bit which is £16+ I think to bleed them, plus potentially more money to spend on the Guides themselves to get the new type caliper.

Ill almost certainly get the Guides secondhand as plenty around but is the new design caliper even much of an improvement?

Cheers guys!

As far as I’m aware there is no change to the calliper it is just a new style bleeding attachment (that originally was on the top spec guides)

My understanding is that the new S4 caliper is the old Guide Ultimate caliper.

Improvements include better seals and heat management (heatsink) apparently.

OK, thanks guys. Bleeding procedure was the main plus for me. That said, the standard Guides aren’t too bad to bleed really.

Thanks again guys.