Quest Q40 Review: A Light, Water-Resistant Machine With a Thin Spec Sheet

A wider aftermarket than most single-brand machines get, which is genuinely valuable if the stock setup does not suit a specific site. Coil makers CORS and NEL both publish coils for the Quest range, which gives an owner options a closed-ecosystem machine does not have. That is a real advantage over a brand with no aftermarket coil support at all, and it is also a sign of how this brand competes: on flexibility and price rather than on a deep published data sheet from Quest itself.

The included headphones are worth calling out specifically, since several rivals near this price, including the Teknetics G2+ and the Fisher F44, do not state headphones in the box at all. Low latency wireless lite headphones included at $326.03 is a genuine value point, provided the low latency claim holds up in practice, which the battery runtime calculator is a reasonable place to sanity-check against a stated rechargeable lithium pack.

Published figures only, and this is the thinnest data sheet in this whole set of reviews.

Included headphones are the one place the Q40 clearly wins this table.

Start with the basic numbers. The listing used here does not state a coil size, an operating frequency, or a numeric target ID range for the Q40, all of which the Nokta Simplex Ultra and several other same-price rivals publish plainly. When a larger, longer-established maker leaves a spec blank, a buyer can sometimes lean on the brand's general reputation and a large body of published third-party reviews to fill the gap. With a smaller brand, that safety net is thinner, and the responsible move is to ask a dealer for the exact coil size and frequency before ordering rather than assuming a typical figure.

Second, "water-resistant" is a specifically weaker published claim than "fully waterproof" or a stated depth in feet. Quest's own listing does not claim submersion, so this is a rain-and-damp-ground machine rather than a wading machine based on what is published here. Compare that against the Nokta Simplex Ultra at almost the same money, which states 16 feet outright.

Third, the low latency wireless headphone claim is genuinely good if it holds up, and it is also the one figure in this listing you cannot verify against a competing brand's published number, because Quest does not state a latency figure in milliseconds. Treat it as a stated feature rather than a benchmarked one until you can compare it directly.

Published owner discussion of the Quest range, where it exists, consistently highlights the light weight and the aftermarket coil options as the reasons people choose it over a bigger name at a similar price. Owners who already use CORS or NEL coils on other machines report an easy transition, since the same third-party makers support this platform.

The recurring caution in published discussion is exactly the gap this review has focused on: buyers researching before ordering report difficulty finding a clear coil size, frequency or waterproof depth from Quest's own materials, and recommend contacting a dealer directly for the specification sheet rather than relying on the retail listing alone. Owners also consistently recommend testing the included wireless headphones for lag against your own ear before committing to them for pinpointing work, which is good practice on any wireless system regardless of brand.

Buy it if:

• You want wireless headphones included in the box at this price, which several rivals do not offer.
• You want the lightest possible build and value ergonomics highly.
• You are open to a smaller brand with aftermarket coil support from CORS and NEL.
• Your hunting is dry land, rain and damp ground rather than wading.

Skip it if:

• You want a published coil size and frequency before ordering, where the Simplex Ultra states both.
• You want a fully waterproof, submersible machine, which this listing does not claim.
• You prefer buying from a maker with a longer published track record and deeper spec sheets.
• You want a numeric digital target ID scale confirmed in writing.