NEMO Disco 15 vs Mountain Hardwear Bishop Pass 15
In short: The NEMO Disco 15 costs $35 less; the NEMO Disco 15 is rated 10 °F colder on the figure each maker publishes; the Mountain Hardwear Bishop Pass 15 saves 5.6 oz.
| Spec | NEMO Disco 15 | Mountain Hardwear Bishop Pass 15 |
|---|---|---|
| Approx. price | ~$300 | ~$335 |
| ISO comfort | not published | 26 °F |
| ISO limit | 16 °F | not published |
| Rating on the label | 15 °F | 15 °F |
| Honesty gap | — | 11 °F |
| Rating standard | ISO 23537 | ISO 23537 |
| Weight | 2 lb 11 oz | 2 lb 5.4 oz |
| Warmth per ounce | — | 0.91 °F/oz |
| Fill | 650 fill power down | 650 fill power down |
| Fill weight | not published | not published |
| Loft budget | — | — |
| Shape | mummy | mummy |
| Shoulder girth | not published | not published |
| Zipper | full | full |
| Shell fabric | 20D recycled polyester ripstop, C0 DWR | 20D ripstop nylon |
| Hydrophobic down | Yes | No |
| Packed size | 6.7 L | not published |
Shaded cells mark the row where one has a measurable advantage. Weight, thickness, girth and shape are left unshaded on purpose: heavier is sometimes tougher, wider is sometimes warmer, and calling a winner on those would be an opinion dressed as a measurement.
What each one does well, and costs you
NEMO Disco 15
- The Spoon cut gives real elbow and knee room without the weight of a full semi-rectangular bag.
- Thermo Gills — two zipped vents over the chest — dump heat without letting a draft onto your torso, which is the usual problem with venting a bag.
- ISO lower limit of 16 °F published, so the 15 in the name is at least anchored to a lab.
- Four sizes including two widths, and the Wide is a genuinely different girth rather than a token.
- $300 for a lab-rated down bag is mid-market, and the Endless Promise version is built to be taken back and recycled.
- 650-fill down means 43 ounces and 6.7 litres packed — heavy and bulky next to the 800-fill Riff.
- NEMO publishes the ISO limit but not the comfort figure, so the number most people should plan around is missing.
- No published shoulder girth or fill weight, which makes it hard to compare against bags that do publish them.
- The Spoon's extra width is warmth you have to heat; it is not the bag for the coldest night of the year.
Mountain Hardwear Bishop Pass 15
- ISO comfort of 26 °F published, on a bag that costs $335.
- Five and a half inches of measured loft — as much as bags costing twice as much.
- The Performance Plus cut adds room at shoulder, hip and knee without going to a semi-rectangular shape.
- RDS-certified 650-fill down and a 20-denier shell that is tougher than the ultralight bags'.
- 37.4 ounces, and 650-fill down means it packs large for its warmth.
- The down is not hydrophobic-treated.
- Mountain Hardwear publishes the comfort figure but not the lower limit, so half the ISO picture is missing.
- Only the Regular's figures were verifiable from published sources; the size run is not tabulated here.