Who should pick Landingi
A media buyer with several offers, each on its own URL, is the clearest fit. The shared block keeps the offer consistent, and Optimize is where the variant test runs on the server. That buyer already has email and a cart somewhere else. They came here for the page and the test.
A single quiet lead page belongs on Build only when the page count and the traffic both fit that tier, and you are not testing. Paying for the testing tier only to publish one page is hard to justify. The limits decide it.
An agency that needs a login per client should look at Scale. Programmatic pages and subaccounts are on that tier. A freelancer publishing inside one brand account can skip it.
Leadpages, Unbounce, or a checkout platform
If a busy month would blow past the visit allowance, look at Leadpages. Every Leadpages plan advertises unlimited traffic. Testing there starts on Grow, as a manual A/B test, which works differently from server-side testing on Optimize. The Leadpages review covers the editor and the billing reputation. Leadpages vs Unbounce is the head-to-head when those two are the shortlist and Landingi is the third name.
If your design needs tighter control than Landingi offers, Unbounce is the better choice. Experiment costs more, and the public threads from people leaving it are about that bill. If you are already on Unbounce, start with Unbounce alternatives and the Unbounce review.
Instapage is the other builder that puts server-side testing inside a visitor allowance, and it does not cap the number of pages. The Instapage review breaks down that allowance, including what the help center says happens when an account exceeds it.
If the page needs to accept payments, look at ClickFunnels or Kartra. Both put the checkout in the same account as the page. A Landingi pop-up can still collect an email address. Orders are processed in ClickFunnels or Kartra.
How I would decide
I would use the trial to design the mobile version, because that step is separate from the desktop page. A G2 review says you have to design the mobile layout manually, because the editor uses absolute positioning. The shared block earns its place when it replaces pasting the same offer onto every URL.
The trial limit is lower than the first paid tier, so a full traffic test has to wait for a paid plan. If the mobile layout is the main worry, compare Unbounce Experiment with Optimize before you buy.