Go with the prong, must less chance of a neck injury and more effective in most cases.
Keep going with the training as well
Jasmine - Female Miniature Poodle - born Aug 15, 2010
Loker Delgado Von Stalworth - Male GSD - born Jan 26, 2012
Koda & Zazu - 6 year old male cats
Alex - Male Cocker Spaniel (rescue) - RIP Cuddlebug 2007-2010