The early disc brakes work very well, IMO, noticeably better than the smaller brakes found in (heavier) later TRs.
I have made a few changes to mine:
New Cunifer hard lines (Moss).
New Teflon/SS soft lines (
TSi).
'Kevlar' pads (also TSi).
Disabled the residual pressure valve (on top of the 5-way that carries the brake light switch).
Converted to DOT-5 (Silicone) brake fluid.
Mounted a mechanically operated brake light switch under the dash, so the brake lights come on <span style="font-weight: bold">before </span>the brakes rather than after.
Combined with the wide, sticky tires, the whole setup works very well for me; and I drive LA-area freeways every day. I don't seem to have any trouble stopping, even when the guy in front of me is smoking his tires (although people behind me do have problems).