Ron you are correct. I did the trial of the Atom3d and found it to be very easy to use. Originally I was going to get the Atom3d version but after using it I decided to do a trial of the Design Expert version. I liked it so much I just went ahead and purchased the Expert. I should have made that a little more clear. If someone doesn't need all of the features of the Professional or Expert editions the Atom3d version is very nice.