LeadEngine.ai now lets you swap out language models the same way you swap drill bits: pick the size, hit the trigger, and get the exact cut you need.
This guide breaks down seven carefully‑chosen models, shows what each one actually does best, and gives you dead‑simple rules for when to deploy them in:
Enrichments – filling every blank field without nuking your token budget
Research – turning monster data dumps into crisp, decision‑ready summaries
Cold‑email copywriting – cranking out hooks that feel human, not robotic
Read on, plug the right model into your workflows, and watch your costs drop while your outputs level up.
Model | Speed | Cost | Context Window* | Best at | Use it for… |
gpt‑4o‑mini | $ | 16k | Budget high‑quality | Daily lead enrichments, A/B copy tests | |
gpt‑4o | $$ | 128k | Fast flagship | Long personalized emails, bulk enrichment runs | |
gpt‑4.1 | $$$ | 128k | Peak reasoning | Complex persona research, multi‑step playbooks | |
gpt‑4.1‑nano | ¢ | 8k | Micro‑tasks | Tag/route leads, quick sanity checks | |
o3 | $$ | 32k | Creative + logic mix | Story‑driven cold emails, SmartSequences | |
o3‑mini | $ | 16k | Rapid drafts | Snappy subject‑lines, short snippets | |
o3‑mini‑deep‑research | $$ | 64k | Focused research | Competitive teardowns, ICP deep dives |
Enrichment accuracy – Better reasoning = cleaner data & fewer false positives.
Research depth – Larger context windows let you paste entire web pages, reports or transcripts and still get coherent summaries.
Cold‑email copywriting – Tone, creativity and personalization quality scale with model IQ (but so does cost).
When to pick: 90 % of the time. Sub‑second latency with GPT‑4‑level smarts for cents.
Shines at:
Bulk firmographic & technographic enrichment (10 k+ rows)
Auto‑writing 1‑sentence personalization snippets for each lead
Rapid spam‑word scrub & tone‑check on draft emails
Tip: set this as the fallback model in automations—you’ll rarely need to escalate.
When to pick: You need GPT‑4.1 quality and speed for high‑volume runs.
Shines at:
Real‑time, fully personalized cold‑email bodies that weave 3‑4 enrichment fields
Extracting unique “hook” facts from long web pages to drop into outreach
Chat‑style assistants that answer prospects instantly without quality loss
Tip: Pair with Lead Loops to iterate subject lines in real time based on reply data.
When to pick: High‑stakes strategy docs, investor‑grade research, or complex multi‑step agent chains.
Shines at:
Building complete ICP dossiers by merging CRM, LinkedIn, and scraped data
Generating multi‑step cold‑email sequences with conditional branching
Deep market or competitor analysis reports for leadership decks
Tip: Offload heavy calls to overnight batches to control spend.
When to pick: Simple classification, deduping, or “does this row pass?” checks.
Shines at:
Yes/No tagging (ICP fit, industry, employee range) on 100 k‑row CSVs
Fast domain sanity checks to weed out spam or free email providers
Quick language cleanup—capitalization, trimming, basic grammar fixes
Tip: Use Nano early in a waterfall: cheap filter first, escalate rows that need brains.
When to pick: You want more personality than 4‑series but still solid logic.
Shines at:
Crafting narrative‑driven cold emails that sound genuinely human
Brainstorming edgy LinkedIn hooks, webinar titles, or ad angles
Writing persuasive PS lines and CTAs that match your brand voice
Tip: Prompt with “Write like Patrick riffing on a podcast” to tap its free‑flow style.
When to pick: Need a lot of variants fast (subject lines, CTAs, SMS).
Shines at:
Generating 25+ subject‑line or SMS variants in under a second
First‑pass technographic guesses before higher‑cost verification
Snappy follow‑up copy or short LinkedIn replies where speed rules
Tip: Fine‑tune your Tone Packs on o3‑mini for instant on‑brand drafts.
When to pick: Deep dives, but your infra timeouts at 10 s.
Shines at:
Summarizing competitor moves after scraping their entire site
Mining customer reviews to surface pain points & feature gaps
Building bullet‑point comparison sheets (Smartlead vs Instantly vs LeadEngine)
Tip: Chain it after a web scrape task; include source URLs for fact‑check output.
Is the task <5 s & <$0.001? → 4.1‑nano
Need speed + solid quality? → 4o‑mini
Need premium quality but still fast? → 4o
Need max IQ or >128 k tokens? → 4.1
Need extra creativity / brand voice? → o3 → o3‑mini if speed required
Need structured competitive research? → o3‑mini‑deep‑research
Waterfall wisely: Cheap model → mid‑tier → flagship. 30–60 % cost savings vs one‑shot 4.1.
Cache enrichment outputs: identical prompts + data = free hits next time.
Profile cold‑email steps: generate subject lines with o3‑mini, body with 4o‑mini, final QA with 4o.
Use system prompts: keep outputs short to control spend (tokens = money).
Q: Can I force a single model for my workspace?
A: No, you set it at the campaign level for each copy variation or enrichment step.
Q: Do models ever disappear?
A: We follow OpenAI’s deprecation schedule. You’ll get a heads‑up and migration presets.
Q: How do I see cost before running?
A: There is no cost estimate provided before running any AI, choose your model and prompts wisely.