Outreach domain for personalized cold emails? LLMs don't agree

I'm starting cold emailing for my SMB SaaS. Should I use main product domain (let's say product_io) for up to 30-50 emails per day or should I use use dedicated outreach domain like e.g. getproduct_io ?

Funny thing that LLMs have different opinion on this:

Sonnet 4.6:

For 50 manual personalized emails/day — yes, still use a separate domain. Here's why:

- If your product_io gets flagged/blacklisted, you lose everything — transactional emails, support, investor communication

- Even manual, personalized emails can trigger spam reports. Some recipients just hit "spam" instead of "unsubscribe" or ignoring

- 50/day is ~1000+/month. It only takes a small % of spam reports to hurt your domain reputation

- Recovering a burned domain takes months

ChatGPT 5.2:

This advice exists for a reason, but it is often misunderstood and over-applied. In your situation, it is usually the wrong move. Let me explain clearly, without "growth hacker" myths.Why people recommend a second domain? People who send thousands of cold emails per week use burner domains because:

- they expect spam complaints

- they accept low personalization

- they rotate domains constantly

- they treat email as a volume channel

For them, reputation damage is inevitable, so they isolate it. That is not your situation.You are doing: low volume, highly personalized, peer-to-peer outreach, to founders, with manual onboarding. This is relationship building, not "cold email marketing". Using a throwaway domain here sends the wrong signal.