Adjustable jets were great----back in the 60s----when we were running lots of 97s on race engines---with methanol, nitro and any other thing we could get. We used like .120 jets and used the adjustable needle to decrease the final jet size. They leak like crazy-----
For the street, don't use adjustable jets.
If in my craziness, I built another engine with lots of 97s on a race only engine, I might use the adjustables again---but that would be the ONLY place for them.