Product review (5 stars): Just the part we needed and not super duper hard to replace
Just the part we needed and not super duper hard to replace.  Just as other reviewers have noted, it would have been much easier with the special spring tool, but we're glad we didn't spend the extra money on it.  Two of us did it together and used 3 screwdrivers to pry the tightening rings around the gasket.  We watched a really great step-by-step tutorial on how to replace it on our laptop as we worked and it took us about an hour and a half.  So glad we saved the $200 professional repair cost!