Probably so as you're going much slower with longer brake applications, for a longer period of time.
RBF600 Fluid is what I use, loads of pads for Mk1 Golf GTi out there that will fit the G40, whatever you pick make sure it's not some endurance pad which requires you to left foot brake for the first 5 miles so they work.
I'd also leave the standard master cylinder on with standard size calipers.