Grant Frichey answers a question:
Questions absolutely drive my blog content and I really liked this one: how does the T-SQL CHOOSE command affect performance.
On the face of it, I honestly don’t think it will affect performance at all, depending on where and how you use it. However, the answer is always best supplied by testing.
Grant’s post ended up being much more interesting than I had anticipated—my anticipated answer was “It’s a CASE statement so it behaves like a CASE statement.” But there is some nuance that I’ve left out.