The verdict
For a small team that wants a predictable stream of enquiries or sales and a channel that scales, pick Meta Ads. It has wider reach and a richer set of tools for measurement.
Pick X Ads for a specific job. If you have content tied to a live topic and your buyers follow that conversation on X, a small paid test can put you next to it. For B2B, X is the cheaper test, but check that your analytics tool and CRM can take its conversion data first.
I would not make X your first paid channel unless your business runs on timely content. Reach on the platform has shifted over the years, so start small and let the results decide.