Xiaomi has only just released the Xiaomi 15 Ultra in China. While the company will not be offering the handset in other markets just yet, a reliable importer is now offering the handset worldwide at a significantly lower price point than Xiaomi is expected to charge globally too.https://www.notebookcheck.net/Xiaomi-15-Ultra-already-available-to-import-worldwide.969354.0.html
There's a Reddit thread dedicated to Giztop, mentioning defective devices being sent to people (including Xiaomi 14 from just a year ago). I'd be wary