I'm not going to be much help at all, because I've only ever brewed the AG version of this recipe, but I just wanted to say, you picked a great beer to brew. I drained this so quickly, it isn't even funny, and it was a huge kick amongst my friends, most of which are BMCers.
Have you done a PM brew before? If not, I would encourage you to try it and challenge yourself a little bit. However, only you can determine if you're ready. As you move on to more and more complex recipes and processes, you need to make sure that you're comfortable with what you're doing before moving on. If you've made a decent beer using an extract + steeping grains, then I would say, up the ante.
As far as taste difference between the two, I can't comment on that.