I use it to conduct thorough online researches. Plug-in some online search MCP (like the one I use: https://jerrysniffs.online ), and the flash models dig through the internet for dirt cheap..

Most of the times, the total cost, including search API's, is less than $0.05 for full deeply researched output, and the research is actually good.

It's been good for one-off cases in my limited experience. I would describe its behaviour as Sonnet-shaped, if that makes sense to you. Good answers but it often decides to reason a lot about simple things before getting to an output.

At the speed Flash has on most providers, it doesn't really turn into a latency concern.

We use it at a moderate scale, self-hosted on B300 hardware. It's great :D

QA analysis of voice transcriptions. Napkin math: we operate at 2-5% of the cost of running on Equiv Frontier, though this changes near-weekly because pricing is so volatile.

It took us about a month to get the inference configured to achieve these numbers. But if you can get your hands on a pair of B300 GPUs and the context works, it's untouchable for price/performance.

(B200 would work, but you don't have the B300's memory, which lets you run it on 2xGPU instead of 4xGPU... with Dspark, it's like magic)

On a side note, for tasks that don't require the intelligence of DS v4 flash, we're using Nemotron-3-super with incredible success. I'm shocked we're not seeing more adoption of this model, given how easy it is to fine-tune and how blisteringly fast the nvfp4 version is. (A single B200 GPU can produce an insane amount of throughput with Nemotron 3 Super.)