Less often than with most tools, because Semrush overlaps with OppAlerts more than anything else on the market. It sells keyword rank tracking, AI prompt tracking, competitor analysis, content optimization and site auditing in one subscription. If that covers your work, a second product is hard to justify. If you manage the software budget, identify the specific research task that would justify the additional subscription.
The answer turns on four reports Semrush does not describe on its pricing page, and on whether you need them.
What you already have
Semrush plans run from $139 to $549 a month. They include 5 to 40 websites monitored, 500 to 5,000 keywords tracked daily, and 50 to 200 prompts tracked daily from the $199 Starter plan up. They also include 300 AI visibility reports a day for any domain. MCP access starts at Starter and API data integration arrives at Advanced.
Site Audit is included, and OppAlerts has no equivalent at all. Keyword research, competitor analysis, cannibalization analysis and multi-location tracking are all deeper there than here.
If you are using most of that, keep it. Nothing below is an argument for replacing it.
The four things that are not in it
These were not found on the Semrush pricing page, and they are where the second product earns its place or fails to.
- Searching for placements by opportunity type. A link gap report finds where competitors got links. It cannot suggest a podcast, an award program or a speaking submission that nobody in your market has taken yet, because it works from links that already exist.
- The contact route each site publishes. Contact pages, addresses, phone numbers and social profiles returned with the prospect, so you can contact the listed prospects without a separate subscription.
- A searchable news, blog and podcast index, queried by meaning as well as keyword, for coverage of your brand and competitors.
- Month-by-month link graph history for a host, its www variant and its domain, so a prospect's direction over years is visible rather than only its current standing.
There is also a difference in content scoring worth understanding rather than counting. Semrush optimizes against what performs for a target term. OppAlerts compares a draft's meaning against a category you select, including audience, industry, product and US city taxonomies. Those answer different questions, and the second is useful when there is no target query to optimize against.
How to decide in an afternoon
Take a client or a market you are working on now and ask three questions.
Does the work end when the report is read, or does someone then have to find publishers, look up contacts and write to them? If it ends at the report, one product is enough.
Are you paying for a prospecting tool, a contact database or a media monitoring subscription alongside Semrush? If so, the comparison is not Semrush against OppAlerts but Semrush plus those tools against Semrush plus this one.
Does your reporting need Perplexity or Claude? Neither product tracks Claude, and OppAlerts does not track Perplexity either, so that requirement points elsewhere entirely.
What is duplicated if you keep both
Keyword tracking and AI prompt tracking, since both products sell them. Price that overlap on a matched workload before deciding it is worth paying twice.
The two meter it differently. Semrush sells a daily entitlement, so 50 prompts a day means 50 each day whether or not you needed them. OppAlerts sells a weekly call allowance, one call per item per provider per day, with the days chosen per item. A team checking a large set twice a week is buying five unused days out of seven under a daily model.
Use your next research assignment to check the overlap. Add a service only when its additional results support work your current setup leaves unfinished.
The full comparison is in OppAlerts and Semrush compared.