Yeah, not sure about the side by side comparison, but I do know LR3 allows for distortion manually on grid too, which is really cool. So even if a specific lens isn't directly supported with preset, you can make your own correction preset.
I've decided against setting up an LR3 discussion topic. In fact all things commercial, e.g. Ad*be, I won't participate in. I was lambasted by users here over the weekend for recommending it. So, whatever. People will figure it out. If they don't, oh well.