tldr; Reddit has mixed feelings about the Sea to Summit Spark; while praised for its industry-leading weight and roominess in Pro versions, some find the Spark 45 too tight or the Pro unsuitable for side sleepers.
$349.00 on AmazonScores based on sentiment analysis of topic-related comments
Best praise vs top criticism for Sea to Summit Spark
“Part of the appeal of the Spark/Flame is the goal to be extremely light, that's why they use the thin shell fabrics, light zippers etc.. You can get beefier models from StS and many other manufacturers. I've been happy with my last gen Spark III and IV.”
“If you can order some bags together and compare loft, I was thoroughly unimpressed with the Spark, compared it to three other bags, Cumulus Panyam 450 and Xlite 400, and ended up choosing a Western Mountaineering Megalite.”
40 Reddit opinions analyzed • Last updated 4/5/2026