Mercer Culinary Genesis Granton Edge Santoku 7 in (M20707): problems, parts and running costs

Checked: 2026-10-19

Summary

The M20707 is a forged high-carbon German-steel santoku that rarely fails; the practical problems are maintenance and expectations. Its HRC 56 edge is easy to hone but needs sharpening more often than harder steels, the “Granton” scallops stop short of the edge so it cuts more like a straight edge, and it is hand-wash only with dishwasher damage excluded from the warranty. Running cost is sharpening supplies only, with no consumable lock-in, and it is a strong buy at the $40–50 street price US restaurant-supply stores list against a roughly $90–105 Genesis list price.

Common problems and fixes

The edge needs sharpening more often than harder steels — HRC 56 is on the soft side of German cutlery, so owners find it easy to hone and sharpen but one roundup lists “needs frequent sharpening” as a con. Fix: hone regularly and sharpen on a stone or steel, and budget for sharpening supplies. The warranty excludes dullness from normal wear. [1][5]
The Granton scallops stop short of the edge — an owner describes scallops that do not reach the cutting edge, so the knife behaves more like a straight edge than a full scallop-to-edge anti-stick design; another reported uneven scallop spacing near the tip on the left face. Fix: treat the scallops as cosmetic release, not a reason to pay a premium. [6]
Hand-wash only, and dishwasher damage is not covered — Mercer warns that heat and caustic detergent degrade the handle and pit or stain the blade, and the warranty excludes dishwasher and harsh-cleaning damage. Fix: hand wash with warm water and mild soap, rinse and dry with a soft towel, and never use a dishwasher, bleach or long soaking. [1][2]
The warranty excludes misuse and normal wear — dullness from normal wear, cutting on glass, marble or hard surfaces, cutting frozen food or bone, opening cans or jars, neglect and unauthorized modification are not covered. [2]
No instrumented edge-retention test exists for this exact knife — no lab test from RTINGS, Wirecutter, CNET, PCMag or Tom’s Guide covers it; Food Network hands-tested 15 santokus and named it Best Mid-Range. Treat edge life as reported rather than measured. [4][9][10]

Parts and consumables

No consumable lock-in — there is no subscription, cartridge or proprietary refill; the knife is not user-serviceable beyond sharpening and honing. [1]

Yearly running cost

The knife is unpowered, so there is no electricity, filter, pod or battery cost. The only recurring cost is sharpening and honing supplies, plus a cutting board or storage. The sources give no prices for stones, steels or sharpeners, so no yearly figure can be computed. Not enough data.

When it is a good buy

US restaurant-supply and specialty retailer snapshots from 2026-10-15: WebstaurantStore listed the M20707 at $39.99–42.49 each [7], CooksDirect at $47.54 [16], ActionSales at $48.25 [17], Wasserstrom at $49.37 against a $90.30 reference price [15], and Just One Cookbook cited a Wayfair price of $50.23 [5]. The Genesis single-knife list runs roughly $86–105, so street prices typically sit well under half of list.

At or below $40: strong value — forged, NSF-certified and lifetime-warrantied, with a hands-on Best Mid-Range placement and a strong owner record.
$41–55: still good value, paying a modest premium over stamped budget santokus for forged construction and a defined warranty.
$56–80: fair to weak, as forged Wüsthof, Victorinox and MAC santokus with deeper test histories become direct alternatives.
Above $80: weak value, at or above Genesis list, where the M20707 gives up the street-price advantage that is its main selling point.

Alternatives:

Wüsthof, Victorinox and MAC santokus — better choices in the $56–80 band when a deeper independent test and ownership history matter more than the M20707’s price advantage. [9][10]
Tojiro — the current Serious Eats best-budget santoku pick; the alternative when a budget pick with editorial backing is the priority. [9]