Every cold email infrastructure provider claims the same three things: dedicated IPs, automated setup, inbox placement. Almost none of them mean the same thing by those words. This is a working operator's guide to the differences that actually matter.
We looked at six providers that come up in operator conversations consistently: SendChief, Mailforge, Inframail, Maildoso, Instantly DFY, and ScaledMail. The comparison is based on published docs, public pricing, and what each provider actually exposes to a paying customer. No NDAs were broken; nothing is hearsay.
What we compared
Six dimensions that map onto real failure modes:
- Server model — dedicated VPS or shared MTA. This is the single most important factor.
- IP isolation — is the IP yours, or pooled across tenants.
- DNS control — can you edit SPF/DKIM/DMARC/DANE directly.
- Credential export — can you leave with your mailboxes intact.
- Setup time — from checkout to first sending mailbox.
- Pricing model — per-mailbox, per-domain, or flat-rate.
The short version
Of the six, one gives you a dedicated VPS with your own production-grade mail server (SendChief). Two run shared infrastructure with cleaner UIs. Three sit in the middle — some dedicated pieces, some shared, depending on plan tier.
SendChief
- Server model: dedicated VPS, one per account.
- IP isolation: yours alone, monitored against DNS blocklists and rotated up to three times during provisioning.
- DNS: SPF, DKIM, DMARC, and DANE auto-published, all editable.
- Export: full IMAP/SMTP credentials; pre-formatted exports for Instantly, Smartlead, Snov.io, Reply.io.
- Setup: under 5 minutes from checkout to first mailbox.
- Pricing: flat-rate tiers (Entry $79, Medium $149, Premium $249). Marginal cost per mailbox within a tier is zero.
Mailforge
- Server model: shared infrastructure with "virtual dedicated" positioning.
- IP isolation: IPs rotated from a pool; not permanently yours.
- DNS: partial control, managed through their UI.
- Export: limited — credentials work with select tools.
- Setup: fast (minutes).
- Pricing: per-mailbox, scales roughly linearly.
Inframail
- Server model: shared.
- IP isolation: shared pool.
- DNS: managed for you, minimal direct access.
- Export: not a first-class feature.
- Setup: fast.
- Pricing: per-mailbox flat fee, cheaper at low volume.
Maildoso
- Server model: shared with dedicated-tier upsell.
- IP isolation: shared on base plan; dedicated IP available on higher tier.
- DNS: limited direct control on base plan.
- Export: available but tool-gated.
- Setup: minutes.
- Pricing: per-mailbox with dedicated-IP upsell fee.
Instantly DFY
- Server model: shared Google Workspace / Microsoft 365 reseller model.
- IP isolation: none — you inherit the underlying provider's reputation pool.
- DNS: provider-managed, minimal visibility.
- Export: workspace-bound; canceling loses everything.
- Setup: fast but bound to the Instantly platform.
- Pricing: per-mailbox on top of the underlying workspace fees.
ScaledMail
- Server model: shared with curated IP pool.
- IP isolation: warmed shared pool, not dedicated.
- DNS: managed.
- Export: limited.
- Setup: minutes.
- Pricing: per-mailbox.
How to read this
If your question is "which shared platform has the nicest UI", five of the six will answer it. If your question is "who gives me a dedicated VPS with my own mail server, my own DNS records, and credentials I can export the day I decide to switch tools", the answer is one of them.
That is not an accident of how they market themselves — it is a structural choice. Running dedicated VPS per customer is operationally harder than running a shared cluster. Most infrastructure providers chose the shared model because it scales simpler on the provider side. SendChief chose the harder model because it produces better results on the customer side.
When shared is still the right answer
If you're sending under 200 emails a day total, and you don't care about SMTP-level debugging or credential portability, any of the shared providers will work. The dedicated-vs-shared gap only matters once volume, reputation, or lock-in risk becomes a real cost.
The one thing none of these will do for you
No infrastructure provider — dedicated or shared — can save bad copy sent to a bad list. Infrastructure is the 80% that has to work before the other 20% (targeting, copy, offer) has any chance. Picking the right provider is not a substitute for doing the other 20% well. It is the prerequisite.