Google Earth Pro is one of my constantly used research tools. The wayback images feature is quite useful. I also use the drawing utility, the image import and stretching feature and the measuring utility quite a bit. I use it in conjunction with another software that has a slope shading (Lidar) layer and historical topos layer. Resolution varies, particularly as a function of vintage, but, even so, can still be useful. Hurricanes can also strip foliage off trees and reveal the understory in semi-tropical and tropical areas. Historical topos can be in dubious register compared to modern stuff.