assistant: For a sub-3 marathon attempt at your weight and fitness level, you're in the sweet spot for a dedicated carbon racer — and you've got three strong contenders here. **The top pick: Puma Deviate Nitro Elite v4.** This is the fastest shoe in the group for your profile. It's lighter (170g) and firmer than its competitors, with a plate that sits higher in the foam and rewards aggressive cadence — exactly what a sub-3 runner needs. EDDBUD calls it "one of the lightest Puma racers ever" and notes it "wants you to pick up the cadence," which aligns with your 6:00/mi tempo pace. Doctors of Running ranked it her #3 shoe of 2026 and praised its "firm but very snappy" ride that "responded really well to faster paces." Fordy also picked it as his fastest marathon shoe. The tradeoff: it's not the cushiest option here, so it demands a confident, fast runner — which you are. **Runner-up: Mizuno Hyperwarp Elite.** If you want a touch more cushion without sacrificing speed, this is it. It's equally light (170g), has maximal cushioning but with a firm, responsive character, and EDDBUD calls it "a dependable, light, and versatile carbon racer" with "excellent grip, durability, and stability." The 3.5mm drop is the lowest in the group, which some runners find snappier; the smooth transition and moderate rocker will help you hold form late in the race. **Third option: ASICS Metaspeed Sky Tokyo.** This is the cushiest racer here (maximal stack, 40mm heel) and the lightest (159g). It's built for stride-focused runners and excels at marathon pace, but it's slightly softer and more compression-driven than the Deviate — better if you want to float through miles 18–26 rather than attack them. All three are priced $250–$275 and built for your neutral gait. The Deviate rewards your cadence and aggression; the Hyperwarp splits the difference; the Metaspeed Sky prioritizes cushion. For a sub-3 attempt, I'd lean Deviate — it's the racer that wants you to run fast.