If the locks are open the tide rips through them. If you are worried about your boat skills you might want to go when they are closed. When they are closed you will wait in front of them. Other boats will be waiting as well. When they open other boats will be coming out, wait for them to exit and then you will enter the lock (with other boats). Once inside you will tie up on the Port or starboard side and wait for the lock to close. Once the lock is closed they will either fill the lock or empty the lock depending on the tide in Peconic.
Passing through with the lock open is not that difficult but, you are going to be on vacation so it might not be worth the headache.