I have a saved flight which opens 2-3 seconds from intercepting the ILS for 4L at JFK, @ 1500 ft, and approx 15 miles out.
The default FS Airliners drop like rocks, nearly hitting the water. Then they struggle back to altitude, doing the FS Wiggle Waggle, left to right, right to left correction of heading attempting to line up.
All add on aircraft do better than the default FS offerings.
One does it absolutely flawlessly! That is the Project Airbus 320's,319's and 318's.
They maintain altitude, line up on the beam with absolutely no wiggle waggle!
Give em a test flight, I think you'll like em