Pros: Easy, light on the system, accurate.
Cons: I have not found one yet.
I used Game Hunter in the past, and it always worked perfectly. Easy to use, intuitive, and accurate. Almost all of my games (except for the truly obscure I own) were identified successfully and added into the catalogue with all proper information.
Although the formatting of the catalogue exported to PDF was not great, it was more than enough even so more when the price tag of this very useful tool is zero.
I enjoyed the program's abilities in cataloging, though I got a bit tired of filling the classifying forms. I like that now I do not have to remember which games I've played – I can see it in the program.