What, that is so weird. This Camera Raw is so simple and it has no extra fluff that would make the program slow. Of course if I need to do more than just adjust the things you see here, then Lightroom will probably be my go to. I do find it a little too extra for simple things, and there is so much stuff on the screen! I have to keep pushing back all those things from left, right, up and down the screen to really get a good look at just the image and not all that stuff.
RE: Reality Check: Before and After Photoshop - Sunsets and Sunrises