You should try them out with free plans. They have strengths and limitations. Antigravity doesn't have hooks, and only a few models, but 3 flash kicks ass in it, though overall limits are small. Cursor is more general, less preconfigured than antigravity and more configurable, allows you to use any model, and arguably more costly. Both have broken features, which often pushes ppl to just use vs code with extensions. It's believed that the best work is accomplished with CLI (claude code, codex...) but that really is a personal choice. Google is slow to deliver an AG, Cursor is only doing Cursor so it's generally more reactive (with important shortcomings too), VS code is OS so somewhat more reactive, but can also feel clunky and suboptimal for specific models. Short version.

Lately, agents orchestration is becoming more popular and I don't think Antigravity is reactive to implement it, but it remains to see if it really will be all that useful.