bp/w! just jump a pool to get a feeling for it. I have always been in a backplate (ok did half of my first pool dive in a jacket) and recently went to Hawaii (of course I had to do some diving) I was "done" with my old wing and just didn't want to deal with it anymore, I went and bought a new Halcyon wing the day before I left. I landed on the island somewhat worried about my night dive the next night with the new wing... As soon as I jumped in the water I asked myself why I hadn't replaced my old wing for the new H sooner!
Ooh.... I just thought, you've never adjusted a plate? get someone to help you do it and you'll have a great experience!