I actually had the opposite problem than other reviewers. Previous versions were sluggish and buggy, but that was before I upgraded to an Intel machine. On my 2.66GHz iMac with 4Gb RAM, v5 has been wonderfully stable and the renderings are fantastic, even clouds. Version 4.x was a bit of a memory hog, and although v5 is supposed to be a leaner application, it still uses just a bit more memory than I would like. Still, it is a nice improvement, and I love all the new configurations. available. It would be a nice feature to be able to select a centering point by dragging rather than by cities or compass points.