Choosing an AI model for business requires testing your tasks, costs, latency and deployment constraints. Compare candidate models on the same evaluation set and check current provider terms before committing.
The question buyers over-weight
Model selection generates more debate than any other decision in an AI project and determines less of the outcome than almost any other. Relative model performance changes over time and by task. Evaluate candidate models alongside retrieval and workflow design rather than assuming that a benchmark ranking predicts your results.
That is not an argument for indifference. It is an argument for spending a week on selection rather than a quarter, and putting the recovered time into evaluation, retrieval and workflow design, where the returns are much larger.
What genuinely differs
The differences that show up in production are rarely about raw capability:
- Cost per unit of work. Prices vary substantially, and at volume this dominates. Model the cost against your realistic monthly token usage, not against list price on a marketing page.
- Latency. For interactive workloads, a slower but slightly more capable model can be the worse choice. Measure end to end, including retrieval, not model response alone.
- Context window. Matters if you routinely process long documents. Note that filling a large window is expensive and often less accurate than retrieving the right passage.
- Structured output reliability. If the model must return valid JSON conforming to a schema, providers differ meaningfully. Test this specifically; it is a common source of production failures.
- Enterprise terms. Retention, training exclusion, regional processing, BAA availability. Frequently the deciding factor in regulated settings, and unrelated to capability.
- Rate limits and reliability. Your ceiling at peak load, and the provider’s incident history.
A selection process that takes a week
-
Build the evaluation set first
Fifty to two hundred real examples from your workflow with known correct answers. This is the asset that keeps paying: it lets you re-evaluate whenever a new model ships, and one will.
-
Test the same prompts across candidates
Identical inputs, identical retrieval, scored on your criteria. Vendor benchmarks are not evidence about your task.
-
Measure cost and latency together
Record tokens and response time per case. Project to your monthly volume before looking at quality scores, because it may eliminate options outright.
-
Check the contract terms
Training exclusion, retention, residency, and whether the required agreements are available on the tier you can actually buy.
-
Design for replaceability
Keep model calls behind an internal interface to reduce the integration work involved in switching providers. Re-test prompts, output schemas and tool behavior before switching.
Frequently asked questions
Should we commit to one provider?
Are open-weight models good enough for business use?
How often should we re-evaluate?
Does model choice affect compliance?
For implementation support, explore our LLM development services or discuss your workflow in a free consultation.
A 30-minute call. Bring one process that costs you real time and leave with an honest answer on whether automating it is worth the money.