Here is how these two sleeping pads compare on the numbers. The Ether Light XT leans on low weight while the Boundary Deluxe Insulated answers with warmth, so the pick comes down to which you value.
| Sea to Summit Ether Light XT | Big Agnes Boundary Deluxe Insulated | |
|---|---|---|
| GearScore | 84✓ | 77 |
| Warmth (R-value) | 4.1 R | 4.3 R✓ |
| Weight | 16.6 oz✓ | 25.0 oz |
| Warmth-to-weight | 0.87 R/100g✓ | 0.61 R/100g |
| Packed size | 1.95 L✓ | 2.57 L |
| Thickness | 3.9 in | 4.3 in✓ |
| Durability | 39 /100 | 60 /100✓ |
| Price | $189 | $180✓ |
| Features | 1Pump sack included | 3Pump sack included, Two-way valve, Repair kit included✓ |
| Type | Inflatable | Inflatable |
| Shape | n/s | Rectangular |
Highlighted cells mark the better spec: Ether Light XT in blue, Boundary Deluxe Insulated in amber. A blank spec is never counted as a win. GearScore is the rating for the Overall use-case (0 to 100). Pick another above to re-score. Prices are current MSRP.
The Sea to Summit Ether Light XT against the Big Agnes Boundary Deluxe Insulated is a study in priorities. The Ether Light XT wins on low weight and warmth-to-weight, and the Boundary Deluxe Insulated pushes back on warmth and cushion.
The Ether Light XT is 8 oz lighter, stronger on warmth-to-weight, and more packable (1.9 L vs 2.6 L). The Boundary Deluxe Insulated is warmer (R 4.3 vs R 4.1), thicker for more cushion, and more durable. On the default GearScore the Ether Light XT leads 84 to 77.
Pick the Ether Light XT if you care most about low weight and warmth-to-weight, which makes it the better call for counting grams on long miles. Pick the Boundary Deluxe Insulated if warmth and cushion matter more to you, or you are focused on colder nights and shoulder-season trips.
The Sea to Summit Ether Light XT. It is 8 oz lighter than the Boundary Deluxe Insulated.
The Big Agnes Boundary Deluxe Insulated. It is warmer (R 4.3 vs R 4.1) than the Ether Light XT.
The Sea to Summit Ether Light XT, 84 to 77 on the default algorithm. You can re-weight the factors to match your trip.
It depends on your priorities. Go with the Ether Light XT for low weight, or the Boundary Deluxe Insulated for warmth. The spec table above shows exactly where each wins.