Just for fun? There’s no benefit in your applications and it just dilutes your study time.
Despite beliefs on CC, there’s no endless, magic X hours = Y points increase equation. Everyone can’t get a 1600/36 just by putting in enough time.
Without data on practice test scores, it’s impossible to comment. My younger D exceeded those scores in 8th grade with no practice. Others won’t get those scores no matter how long they study.