Qwen3.8 Flash vs Muse Spark 1.3 (thinking)
Should you write with Qwen3.8 Flash or Muse Spark 1.3 (thinking)? On this page the only thing that changes is the model. Both wrote their own version of the scripts behind 10 of my What's AI videos, five drafts per script, and four judges (three LLM judges from three model families plus Jev, a typed judge from TypeSafe) scored every draft blind, with my finished script as the reference. Qwen3.8 Flash leads overall, 83.2 to 82.5. Their per-model Elo intervals overlap on this board.
The verdict
Basically a tie, reached in opposite ways. Qwen3.8 Flash is #79 and Muse Spark 1.3 (thinking) is #83, their Elo intervals overlap, and their overall scores are 0.7 apart. Muse is the better writer on most of the page: it leads on six of the nine metrics, including Continuity & Emotion and Tone & Voice Match by about three points each. Qwen wins it back on Length Adherence, by about twenty-nine points, because Muse misses the target length so often. Qwen is cheaper, about a cent a script against four, but takes almost six minutes against just over one. If you'll fix length by hand, Muse gives you better raw material. If you won't, take Qwen.
Pick Qwen3.8 Flash when you want scripts that land on length without editing.
Pick Muse Spark 1.3 (thinking) for better-flowing drafts, if you'll trim or pad them yourself.
How to read these numbers
Overall vs Elo. Overall is the weighted rubric score. Elo compares each model's five-draft average with every other model's, script by script, and counts gaps inside run-to-run noise as draws, so it rewards winning often and can disagree with overall.
Reading the Elo intervals. Each 95% range comes from resampling every model's recorded run scores on each task and re-ranking. Comparing these separate ranges does not test the Elo gap between two models: far apart is strong evidence, and overlap isn't a tie. The tasks stay fixed, so the ranges say nothing about new tasks (the long version).
Metric by metric: where the gap comes from
Blue is Qwen3.8 Flash, orange is Muse Spark 1.3 (thinking), and the solid bar takes the metric. The weight under each name is how much it counts toward the overall. Weighted by how much each metric counts, Length Adherence does the most to put Qwen3.8 Flash ahead: it leads there by 28.6 points. If you care about one thing, say voice or length, go straight to that row.
Cost, speed, and consistency
Quality is half the decision. The other half is what each script costs you, how long you wait, and how often you get a bad draft. Qwen3.8 Flash is ahead and it's also the cheaper one: Muse Spark 1.3 (thinking) costs about 3.2x as much per script.
| Qwen3.8 Flash | Muse Spark 1.3 (thinking) | |
|---|---|---|
| Overall / 100 | 83.2 | 82.5 |
| Writing Elo | 1676 | 1629 |
| Score spread across drafts (± overall std) | 1.920 | 2.600 |
| Cost per script (USD) | 0.013 | 0.041 |
| Avg time per script (min) | 5.7 | 1.3 |
| Open weights | No | No |
Green wins the row, and for spread, cost and time, lower wins. Cost is one script at recorded list prices, uncached and without judging, so your real bill will differ. Spread is how much the overall score moves across a model's drafts, and time is the average time to get one accepted script, retries included.
Want the script-by-script detail? Full scorecards: Qwen3.8 Flash · Muse Spark 1.3 (thinking). The whole scoring pipeline is on the methodology page.
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