We did some unofficial, unmeasured trials, in a 737-300 simulator using a dry runway and then a slippery (ice patches) runway high speed rejected take off. In the case of the dry runway, spoilers and brakes only were used and as expected stopping distance on the dry runway was excellent and there was plenty of runway remaining. The brakes were very hot afterwards. Repeated this time with slippery runway and we left the runway at 40 knots (10,000 ft runway sea level 15C)
Then with slippery runway we did full reverse, max manual brakes and spoilers, and pulled up with 200 metres to spare. It was obvious the full reverse with its significant deceleration effect effort at high speed was the key to stopping short on a slippery runway-ice patches, wet, contaminated) etc especially as the braking efficiency of the brakes themselves was a lot less on the slippery runway. From my experience I would much rather be flying a aircraft with thrust reversers than a brakes only aircraft.