assistant: You're in a solid position — 25 mi/wk with an 18-miler done means you've got the aerobic base. For a 4:30 marathon build-up, you need a shoe that handles easy-to-moderate paces well (most of your training) but also feels responsive enough for your tempo and long-run work. As a heel striker at 85 kg, you'll want solid cushioning and a forgiving landing — something that won't punish your heel strike on high-mileage weeks. A maximal-cushion daily trainer is your sweet spot here, not a racing flat. **Saucony Endorphin Azura v1** is my top pick for your build-up. It's $150, versatile across easy to tempo paces, and The Run Testers call it "firmer, bouncier, more rockered" — that rocker geometry is friendly to heel strikers because it smooths the transition from landing to push-off. At 244g it's light enough to feel responsive on faster efforts, but the high cushioning (41/33mm stack) absorbs the impact load your heel strike generates. True to size, good lockdown. **ASICS Megablast v1** is a close alternative if you want maximum cushioning — 45/33mm stack, genuinely bouncy per Run Moore, and excellent for easy and long runs. The trade-off: it's narrower in the forefoot, so check your toe-box fit. At $225 it's pricier than the Azura, and some reviewers find it almost *too* bouncy for tempo work, but it's durable (400+ miles) and a solid marathon-training workhorse. **On Cloudmonster Hyper LightSpray v3** is a wildcard. It's expensive ($280) and firmer than it looks, which means it rewards faster paces — great for your tempo and long-run work — but Doctors of Running flags it as "unforgiving for easy runs." For a 4:30 marathoner doing mostly easy miles, this could feel harsh on recovery days. Save it for later if you want a race-day option. <details> <summary><strong>Why the Azura for build-up</strong></summary> The Azura's 8.0mm drop and rocker geometry are biomechanically friendly to heel strikers — you get a smoother transition without the jarring impact of a low-drop shoe. The PWRRUN PB foam (PEBA-based) is responsive but forgiving, and at $150 it leaves budget room to rotate in a second shoe if needed (many marathoners train in 2–3 shoes to extend durability). It covers easy, tempo, and long-run paces without forcing a compromise. The Megablast is heavier on cushioning and slightly bouncier, which some heel strikers love — but the narrower fit and "almost too bouncy" feedback from reviewers suggest the Azura is the safer first choice for your build-up. </details> One follow-up: are you planning to race the marathon in a different shoe (a lighter racer), or do you want your build-up trainer to *also* work as your race-day shoe?

assistant: Got it — you're building durability and staying healthy through 16+ weeks of training, not chasing a time goal. That's the smart first-marathon mindset. For your build-up, **Saucony Endorphin Azura v1** remains my top pick. At $150, it's the best value here and handles the full spectrum of your training paces — easy runs, long runs, and the occasional tempo work. The 8.0mm drop and rocker geometry work naturally with your heel strike, and PWRRUN PB foam is responsive without being jarring. Run Testers calls it "firmer, bouncier, more rockered," which translates to smooth transitions and good energy return when you pick up the pace. **ASICS Megablast v1** is your max-cushion option if you want maximum impact protection on high-mileage weeks. It's 45/37mm stack (vs. the Azura's 41/33mm), genuinely bouncy, and durable to 400+ miles — important for a marathon build-up. The trade-off: narrower forefoot fit and Run Moore notes it's "almost too bouncy" for easy runs, so it shines more on long runs and tempo work than recovery days. **New Balance 880 v15** is a solid third if you want something more structured and traditional. Doctors of Running highlights its "excellent stability for a neutral shoe" and "pronounced rocker geometry" — that rocker will feel familiar to your heel-strike pattern. At $140 it's the cheapest option and a dependable workhorse, though it's the firmest of the three, so it won't feel as plush on easy miles as the Azura or Megablast. <details> <summary><strong>Why the Azura wins for marathon build-up</strong></summary> At 85 kg with a heel strike, you're loading your heel and calf on every footfall. The Azura's combination of high cushioning (41mm heel stack), a rocker that smooths your transition, and an 8.0mm drop that's forgiving without being excessive makes it the most biomechanically friendly choice for 16 weeks of training. It's also $75–$85 cheaper than the Megablast and Cloudmonster, leaving budget room to rotate in a second shoe if durability becomes an issue. The "excellent" expert reception reflects its versatility — it doesn't force you to compromise on any training phase. </details> Are you thinking of rotating two shoes during build-up, or sticking with one workhorse?