It is very possible that the Sony lens is better optically than the old Minolta lens, however, short lenses are easier to use than telephoto lenses generally (greater depth of field, less subject to camera shake induced motion blur), and that might also account for some of the difference. I don't know anything about the Sony lens lineup, but, depending on how old your current tele-zoom is, there may be a newer version with better engineering. The other thing that is in play here is that Todd and I are using lenses that retail new for over $1000.00, and if I remember correctly,Tony Zappia is shooting a 300 F:2.8 which retails over $3000.00. There is a reason folks are willing to pay for those lenses. The optics are noticeably better than the kit lenses. You can get very acceptable results with the kit lenses, but it is a bit unfair to compare them head to head with the "pro" lenses. Pro lenses for Canon and Nikon at least, are usually available previously owned for about 3/4 to 2/3 retail price. Same may be true for Sony.