I find sparrows to be fine up until 12.7, with 13.0 really stretching it in lieu of current BR compression.
Test-fly an F/A-18 with nothing but 7Ps. Specifically on the 18C Late, they will pull up to 180-degree turns at certain speeds and aspects against the target MiGs. They have WAY too much HOBS capability, even if only rated at 25G overload in the stat card. One I fired damn near did a 270-degree turn (with a constant lock on a MiG) and only lost lock after the seeker went out of FOV. My guess is they have way more overload than they are stated to have, or way more seeker FOV than they should.
That certainly isnt intended behaviour nor how they acted when i last played them. So either bug or issues on your side of client.
Let me get back to you once I have chance to test them in lie game today.