# Referral Rock vs GrowSurf: which do AI models recommend for loyalty, September 2026

GTM AI Recommendation Index, September 2026 Edition, Loyalty, advocacy and referrals. Three of twelve models named Referral Rock first on the direct prompt; two named GrowSurf. Page: https://gtm-ai-index.com/marketing/loyalty-advocacy-and-referrals/referral-rock-vs-growsurf/

| | First-choice share | Rank | Negative rate | Labels | Models naming it |
|---|---|---|---|---|---|
| Referral Rock | 22% | #2 of 18 | 0% | 23 | 9 of 12 |
| GrowSurf | 5% | #4 of 18 | 0% | 14 | 10 of 12 |

## The direct prompt, model by model

- MiniMax M2.5: both first (first choices: GrowSurf, Referral Rock) (alternatives: FirstPromoter, Kademi, Zinrelo)
- Gemini 3.5 Flash: referral rock first (first choices: Referral Rock) (alternatives: Annex Cloud, Influitive, PartnerStack, SaaSquatch)
- Kimi K2: referral rock first (first choices: Referral Rock, Zinrelo) (alternatives: Kademi, PartnerStack)
- Mistral Small: growsurf first (first choices: GrowSurf) (alternatives: PartnerStack, True Loyal)
- Claude Haiku 4.5: neither first, one named (first choices: CustomerGauge) (alternatives: GrowSurf, Referral Rock, Salesforce Loyalty Management, Zinrelo)
- Grok 4.1 Fast: neither first, one named (first choices: Influitive) (alternatives: Ambassador, Referral Rock, TrueLoyal)
- DeepSeek V4 Flash: neither first, one named (first choices: Ambassador) (alternatives: CustomerGauge, PartnerStack, Referral Rock)
- Llama 4 Maverick: neither first, one named (alternatives: GrowSurf, Referral Rock)
- GPT-5.4 mini: neither named (first choices: Ambassador) (alternatives: CustomerGauge, Referral Factory, Salesforce Loyalty Management)
- Perplexity Sonar: neither named (first choices: CustomerGauge, Open Loyalty) (alternatives: Talon.One)
- Qwen 3.7 Flash: neither named (first choices: Influitive) (alternatives: Ambassador, CustomerGauge)
- GLM 4.7 FlashX: neither named (first choices: True Loyal) (alternatives: Annex Cloud, Open Loyalty, Yotpo Loyalty & Referrals)

## What the models said about Referral Rock

- "Top Pick: Referral Rock ... highly regarded for mid-market B2B companies because it is built to handle the complexity of longer B2B sales cycles" (Gemini 3.5 Flash, direct prompt, first choice)
- "For most mid-sized B2B companies, I'd recommend starting with Referral Rock for its focused referral capabilities and reasonable pricing" (Mistral Small, paraphrase prompt, first choice)

## What the models said about GrowSurf

- "I'd recommend Referral Rock or GrowSurf as your top choices" (MiniMax M2.5, direct prompt, first choice)
- "Best Overall for Mid-Market B2B: GrowSurf" (Mistral Small, direct prompt, first choice)

Share is the count of first choices across the direct, paraphrase, budget and scale prompts over all twelve models, for a mid-market B2B company; rank is within the category. Comparisons are drawn for the top eight products in each category. Published under CC BY 4.0; the output is the models' output, and nothing here is a recommendation by the index.