Four different cat breeds on an autumn ranch fence with red leaves: Sol 6 looks up, Mistral Large 4 and Gemini Flash look sideways, and Minimax M3 looks down

New models tested: Sol 6, Mistral Large 4, MiniMax M3, and Gemini Flash-Lite

Summary

Newer doesn’t always mean better. “Flash” doesn’t always mean faster.

Sol 6 is cheaper and faster than Sol 5.6, with similar overall quality. In my opinion, MiniMax M3 and M3.1 Flash are not worth using: Luna 6 has better overall quality at a lower cost. Mistral Large 4 does well on extraction, while Gemini Flash-Lite leads on speed.

Sol 6: a cheaper, faster upgrade

Sol 6 is a solid upgrade over the already strong Sol 5.6 in cost and speed. Overall quality is close, and the gains are uneven across tasks.

All five workloads, current run

modelmean qualitycost / tasklatency
GPT-6 Sol0.944$0.03612.2 s
GPT-5.6 Sol0.939$0.08119.8 s
GPT-6 Luna0.919$0.001917.0 s

Sol 6 scored higher on architecture and matching. Sol 5.6 scored slightly higher on repository implementation, extraction, and research. On repository implementation, Sol 6 was faster: 19.8 seconds versus 26.4 seconds.

My takeaway: A cheaper, faster upgrade, with similar overall quality.

MiniMax M3 and M3.1 Flash: not worth using

In my opinion, MiniMax M3 and M3.1 Flash are not worth using. Luna 6 has better overall quality and costs less. MiniMax Flash scored higher on coding, and M3 scored slightly higher on matching, but Flash was slower than M3 on four of the five workloads.

All five workloads, current run

modelmean qualitycost / tasklatency
MiniMax M30.793$0.01326.9 s
MiniMax M3.1 Flash0.865$0.007352.9 s
GPT-6 Luna0.919$0.001917.0 s

On repository implementation, M3.1 Flash averaged 145.2 seconds, compared with M3’s 79.7 seconds and Luna 6’s 30.9 seconds. That makes MiniMax Flash almost 5× slower and nearly 5× more expensive than Luna 6 on this workload. MiniMax Flash completed 13 of the 16 coding responses. M3.1 Flash scored better than M3 on coding and architecture, while M3 scored better on extraction and matching.

I would not recommend them unless you have your own idle GPUs or need to keep your data in your own environment. I have not tested their self-hosted performance or cost.

My takeaway: Luna 6 offers better overall quality at a lower cost.

Mistral Large 4: strong on extraction

Mistral Large 4 is a competitive model for tasks like extraction, matching, and research, but it is slow. If you’re in the EU and looking for a model developed within the EU, it is an option to consider.

All five workloads, current run

modelmean qualitycost / tasklatency
Mistral Large 40.894$0.04353.6 s
GPT-5.6 Sol0.939$0.08119.8 s

Mistral Large 4 scored 0.96 on extraction, ahead of Sol 5.6 and Luna 6. On repository implementation it scored 0.72, compared with Luna 6’s 0.80, while taking 102.2 seconds versus Luna 6’s 30.9 seconds. It was slower than Sol 5.6 on all five workloads.

My takeaway: An EU-developed option worth considering for extraction, if speed is less important.

Gemini 3.1 Flash-Lite: speed for simpler tasks

While Gemini 3.1 Flash-Lite is not a recent release, I finally got a chance to test it too and compare it with MiniMax M3.1 Flash and others. My first impression: Gemini 3.1 Flash-Lite is really fast.

If you need high speed for relatively easy tasks, it is a good option to consider. It could even be useful for simple, well-validated tasks in CI/CD pipelines.

All five workloads, current run

modelmean qualitycost / tasklatency
Gemini 3.1 Flash-Lite0.761$0.00443.6 s
GPT-6 Luna0.919$0.001917.0 s

Flash-Lite was the fastest model on all five workloads, averaging about a second on matching and 7.2 seconds on repository implementation. Its extraction score was 0.82, compared with Luna 6’s 0.90. The CI/CD suggestion is a use case to explore, not something this benchmark directly tested.

My takeaway: Speed for simpler tasks, with validation.

Testing results

$0.001$0.003$0.01$0.03$0.1$0.30.60.70.80.91.0mean candidate cost per task, log scale, cheaper to the rightmean qualityGPT-6 Sol: quality 0.944, cost per task 0.0356954Sol 6GPT-5.6 Sol: quality 0.939, cost per task 0.0805376Sol 5.6GPT-6 Luna: quality 0.919, cost per task 0.0019136Luna 6Mistral Large 4: quality 0.894, cost per task 0.0431788Mistral Large 4MiniMax M3: quality 0.793, cost per task 0.0126666MiniMax M3MiniMax M3.1 Flash: quality 0.865, cost per task 0.0073258MiniMax FlashGemini 3.1 Flash-Lite: quality 0.761, cost per task 0.0044384Gemini Flash-Lite
Quality and candidate cost per task. Better value is up and to the right.
1s3s10s30s100s0.60.70.80.91.0mean model response latency, log scale, faster to the rightmean qualityGPT-6 Sol: quality 0.944, latency ms 12220Sol 6GPT-5.6 Sol: quality 0.939, latency ms 19820Sol 5.6GPT-6 Luna: quality 0.919, latency ms 16980Luna 6Mistral Large 4: quality 0.894, latency ms 53600Mistral Large 4MiniMax M3: quality 0.793, latency ms 26860MiniMax M3MiniMax M3.1 Flash: quality 0.865, latency ms 52920MiniMax FlashGemini 3.1 Flash-Lite: quality 0.761, latency ms 3600Gemini Flash-Lite
Quality and model response latency. Faster models are farther right.

Full results

modelmean qualitycost / tasklatencyArchitectureRepository implementationNoisy extractionSemantic matchingGrounded research
GPT-6 Sol0.944$0.03612.2 s0.9700.9000.9100.9900.951
GPT-5.6 Sol0.939$0.08119.8 s0.9370.9050.9240.9670.961
GPT-6 Luna0.919$0.001917.0 s0.9530.8040.9000.9680.969
Mistral Large 40.894$0.04353.6 s0.8650.7210.9590.9680.958
MiniMax M30.793$0.01326.9 s0.6200.6740.8900.9730.811
MiniMax M3.1 Flash0.865$0.007352.9 s0.8680.8270.8630.9460.820
Gemini 3.1 Flash-Lite0.761$0.00443.6 s0.4720.6890.8230.9390.882

Some responses were unavailable. Costs and latency describe successful model responses.

Methodology

We tested five workloads with eight cases per workload, repeated twice. Sonnet 5.5 graded responses against task-specific criteria; quality scores measure rubric performance, not task pass rates.

The charts give equal weight to all five workloads; costs exclude judging and setup.

Benchmark on your own workloads

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