I like the Busiek run in general but the Kang Dynasty was marred by extremely poor artwork by Dwayne Turner. There are a few individual issues that hit the mark Issue 48 and especially 51 but it could have been trimmed by at least 4 issues without any problem.
As far as George Perez's art is concerned I felt that the only problem with it came in later issues where he contributed layouts rather than full pencils, it was blindingly obvious how much of a difference that made to the book overall.
Generally though the Busiek run is very good but not quite in the league of the Thomas/Englehart/Conway/Shooter/Michelinie era title, and most damning of all for me is the inclusion of one of my least favourite characters in Firestar. I'd prefer She-Hulk, and I hate She-Hulk!
Don't think cos I understand, I care!