The International Handbook of Evaluated Criticality Safety Benchmark Experiments includes thousands of criticality safety benchmark configurations that have been collected since the early 1990s. Their quality and uncertainty analysis have greatly expanded over the years, as computer codes have also expanded and accelerated. Along with the increase in effort required for benchmarks today, the cost of performing experiments has also gone up. This paper evaluates plutonium fast metal and highly enriched uranium fast metal experiments for their major uncertainty contributions and identifies where to focus efforts in future experiment design.