Thats a tough one to answer as i fish needles differently from lots of folks I guess.Of course there is the standard way of picking the right weight for the appropriate water an slow waking em on top.
Sometimes I just let em sink to the bottom an crawl em taking a LONG time to retrive the plug.Sandeels spend lots of time in the sand big fish like it down there also.I may just drag it on the bottom.an leave it there.The other reason i use em is to get em way out there to reach spots i might not be able to reach with a swimmer.If I am fishin a boulder field with lots of fishy spots in close with hangup style bottom I will go to the swimmer.So I can probe all the area's more thoughly that i might not be able to fish with the needle.They are both tools.u hold it an I'll hit it
It's like asking me to decide wether i like Ice cream or cake.
The answer is both of course.