Laguna XS 2.1 (free) vs 
Riverflow V2 Fast
Laguna XS 2.1 (free) has a larger context window than Riverflow V2 Fast (262K tokens vs 8K tokens).
Written rounds
1 promptBuy-side IC memo on a fictional SaaS company. Valuation, then the diligence questions.
Price and specs
Not enough votes to call it. On the specs, Laguna XS 2.1 (free) has the edge: newer, bigger context window.
| Spec | Laguna XS 2.1 (free) | Riverflow V2 Fast |
|---|---|---|
| Input price | Free | — |
| Output price | Free | — |
| Context window | 262K tokens | 8K tokens |
| Free API (OpenRouter) | Yes (1 provider) | No |
| Released | Jul 2026 | Feb 2026 |
| At 10M a month | $0 | not listed |
Input tokens at list price. No caching, no batch discount.
Where to run it
Laguna XS 2.1 (free)1 host
Riverflow V2 Fast1 host
Per million tokens. Prices and uptime via OpenRouter, checked 10 Oct 2026.
Common questions
What is the difference between Laguna XS 2.1 (free) and Riverflow V2 Fast?
Laguna XS 2.1 (free) is developed by Poolside while Riverflow V2 Fast is developed by Sourceful. Laguna XS 2.1 (free) has a 262K token context window vs Riverflow V2 Fast's 8K. You can compare their actual outputs across 1 challenges on Rival to see how they differ in practice.
Which is better, Laguna XS 2.1 (free) or Riverflow V2 Fast?
It depends on your use case. Laguna XS 2.1 (free) and Riverflow V2 Fast each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 1 challenges so you can judge which fits your needs best.
How can I compare Laguna XS 2.1 (free) and Riverflow V2 Fast on Rival?
This page shows a side-by-side comparison of Laguna XS 2.1 (free) and Riverflow V2 Fast across shared challenges. You can vote on which model produced the better output in a blind duel. Browsing and voting are free. No account is needed to look; signing in only saves your votes and likes.
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