It's really not fast enough to count as a mixup, and even if you do land hits comboing on it isn't great (especially with the added ground recovery from your youzansen)
As for using it low in the air to mix up, I think it can be used most often off of a low j.P. After a low j.P they will only expect you to land or do another air move immediately, so the added time they need to block high will throw them off. It also makes you way more safe against characters like pot who might try to IB your j.P and pot buster you as you land, or IB backdash potbuster.