Here is the full list of all 25 Gamer Stats Pro achievements.
You own more than 5 games
You own more than 10 games
You own more than 100 games
You own more than 500 games
You own more than 1000 games
More than 5 games installed
More than 10 games installed
More than 20 games installed
More than 50 games installed
More than 100 games installed
>4h in one session
>8h in one session
>12h in one session
[...]
More than 10 gaming sessions tracked
More than 50 gaming sessions tracked
More than 100 gaming sessions tracked
More than 500 gaming sessions tracked
More than 1000 gaming sessions tracked
More than 10 hours tracked
More than 50 hours tracked
More than 100 hours tracked
More than 250 hours tracked
More than 500 hours tracked