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Erika
Erika

Posted on AI-assisted

I Compared GPT-6 Luna With Four Flash Models

There are many new “Flash” models now.

The name usually means lower price and faster inference. But it is not one standard class. The models have different sizes, context windows, reasoning modes, and benchmark settings.

I wanted a simple comparison, especially after GPT-6 Luna became another low-cost option.

One disclosure: I work with Token Harbor. The benchmark data below is not from Token Harbor. I used current Artificial Analysis results and linked the sources. Token Harbor access is listed separately.

Quick scorecard

These are current Artificial Analysis Intelligence Index v4.3.2 results checked on September 24, 2026.

Model AA Intelligence Index AutomationBench-AA Terminal-Bench 4.0 SciCode AA-LCR v1.1
GLM 5.3 Flash 42 60% 33% 52% 80%
Qwen3.8-Flash-Next 40 56% 25% 51% 80%
DeepSeek V4.1 Flash (max) 39 69% 27% 52% 84%
GPT-6 Luna (xhigh) 34 48% 8% 52% 80%
MiMo V2.6 Flash Not scored yet

GLM has the highest composite score. DeepSeek has the best AutomationBench and long-context result in this group. Qwen stays close to both. Luna is lower on the composite score, but it is very cheap and fast.

MiMo needs a note. Artificial Analysis has a score of 46 for MiMo V2.6 Pro, not Flash. I could not find an independent AA Intelligence Index result for MiMo V2.6 Flash. So I left it blank instead of copying the Pro score.

A second model score

LLM Stats has a separate composite score. It is not the AA Intelligence Index, so I did not mix the two numbers.

Model LLM Stats Score
DeepSeek V4.1 Flash 48.7
Qwen3.8-Flash-Next 48.6
GLM 5.3 Flash 48.2
MiMo V2.6 Flash 45.7
GPT-6 Luna 44.5

This score tells a similar story for the three open Flash models: DeepSeek, Qwen, and GLM are very close. MiMo and Luna follow, with Luna having the lowest input price in the group.

Price and context

Model Context in AA Input / 1M Output / 1M Weights
GLM 5.3 Flash 1M $0.15 $0.50 Open
Qwen3.8-Flash-Next 256K $0.15 $0.47 Open
DeepSeek V4.1 Flash 1M $0.30 $1.20 Open
GPT-6 Luna 1M $0.10 $0.50 Proprietary
MiMo V2.6 Flash 1M* $0.14* $0.28* Open

*MiMo values are from Xiaomi, because AA has not published an independent Flash profile yet.

The Qwen naming is also confusing. Alibaba calls the API model Qwen3.8 Flash. Artificial Analysis tests the related Qwen3.8-Flash-Next checkpoint and reports a 256K context window. A hosted route may expose a different limit, so I would check the provider page before sending a very large prompt.

What the scores mean to me

GLM 5.3 Flash: best overall score

GLM is first here with 42. It also has the best Terminal-Bench 4.0 result at 33%.

It looks like the safest general choice when I want one Flash model for mixed work. The downside is speed. Artificial Analysis measured it much slower than DeepSeek in the tested endpoints.

DeepSeek V4.1 Flash: strongest agent result

DeepSeek is third on the total score, but it leads AutomationBench-AA at 69% and AA-LCR at 84%.

That is more useful than the total score for some workloads. For an agent using tools or reading a large codebase, I would test DeepSeek early.

Qwen3.8 Flash: close and inexpensive

Qwen scores 40, only two points behind GLM. Its list price is also a little lower.

It does not win the rows in this small table, but there is no large gap. It may be a better fit when speed and cost matter more than the last benchmark point.

GPT-6 Luna: fast, cheap, but not the score leader

Luna xhigh scores 34. Its AutomationBench result is 48%, and Terminal-Bench 4.0 is 8%.

This does not make Luna useless. It is a proprietary model made for inexpensive, high-volume work. Artificial Analysis measured around 153 output tokens per second. Its measured cost per Intelligence Index task was only $0.04. I see it more as an implementation and background-task model than the first choice for difficult terminal work.

MiMo V2.6 Flash: interesting, but wait for independent scoring

Xiaomi reports several strong numbers for MiMo V2.6 Flash:

Xiaomi-reported benchmark Score
CyberGym 95.1%
Terminal-Bench 2.1 87.6%
OSWorld-Verified 80.8%
Toolathlon-Verified 73.6%
DeepSWE 1.1 67.9%
AutomationBench v1.0.6 52.3%
Terminal-Bench 4.0 28.8%

It also has a 1M context window and very low list price.

Those numbers are from Xiaomi, not Artificial Analysis. They are useful, but I would not put them in the same ranking table yet. In particular, AutomationBench v1.0.6 is not the same label as AutomationBench-AA. The rank labels in the collected list also need a defined comparison set, so I did not repeat them here.

A separate vendor-reported comparison

I found two benchmark names reported for all five models. This gives a wider view, but the results are not as clean as the independent AA table.

Vendor-reported benchmark MiMo V2.6 Flash DeepSeek V4.1 Flash Qwen3.8 Flash GLM 5.3 Flash GPT-6 Luna
DeepSWE 1.1 67.9% 74% 59% 63% 67%
Agents' Last Exam 27.6% 32% 51% 26% 51%

These are directional, not a strict leaderboard. Each vendor used its own harness, context limit, effort setting, and reporting setup. DeepSeek used maximum reasoning and a 1M-token context for DeepSWE. Qwen reports the best of two harnesses with 256K context. GLM used mini-swe-agent with 400K context. OpenAI reports Luna's highest result across an effort sweep.

The results still show something useful. DeepSeek has the strongest published DeepSWE number in this group. Qwen and Luna have the highest published Agents' Last Exam result. MiMo and Luna are almost tied on DeepSWE.

Other vendor benchmarks do not cover all five models. Some interesting examples are DeepSeek's 91% on Terminal-Bench 2.1, GLM's 78% on Toolathlon, Qwen's 92% on LiveCodeBench v6, MiMo's 95.1% on CyberGym, and Luna's 53% on OSWorld 2.0. I kept them out of the main scorecard because they do not form a complete comparison.

Trying the models on Token Harbor

Three models currently have free routes:

Model Token Harbor model ID Access
MiMo V2.6 Flash mimo-v2.6-flash:free Free allowance
DeepSeek V4.1 Flash deepseek-v4.1-flash:free Free allowance
Qwen3.8 Flash qwen3.8-flash:free Free allowance
GLM 5.3 Flash glm-5.3-flash Agent Pass / paid route
GPT-6 Luna gpt-6-luna New route; check current plan

So the five models are not all free. I think this should be clear before anyone signs up.

For a quick test, I would use the same prompt, reasoning setting, tool schema, and output limit. I would record success, latency, tokens, and corrections. One leaderboard number is useful, but it cannot tell which model will work best with a specific agent harness.

My short choice

  • For general quality: GLM 5.3 Flash.
  • For tool use and long context: DeepSeek V4.1 Flash.
  • For low-cost fast work: Qwen3.8 Flash.
  • For a proprietary high-throughput route: GPT-6 Luna.
  • For a new low-cost open model: MiMo V2.6 Flash, but I want independent AA data first.

The gap between GLM, Qwen, and DeepSeek is small. I would not choose only from the total score. The benchmark row closest to the real task matters more.

Sources

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