Meso_z:
Those were good breaking in sets (3). Next workout slap another 25lb plate, on each side (total 50lbs), and settle in for some serious work. The idea is to tax the body way beyond it normal workout capacity. Using a squat weight that would normally be used for 10 good reps and taking that to the full 20 targeted reps. If done correctly, than another set would be questionable and a third one, nearly impossible. The CNS may rebel.
Beginning with three deep breaths/gasp (through the mouth). Nearing the end of the 20 rep set, you may be taking 5 or 6 breaths (or more) between reps. This program is very demanding on the mental, as well as the physical, strength of will power. The chest may feel like it may burst open. Breathing squats are akin to the Rest-Pause idea. The rib box should be quite sore the next few days after this type of extreme workout. Try adding at least 5lbs (2 1/2 each side) with each following training session. The progressive workout load is one of the major concepts of this type training,when training with very serious intent. If feeling dizzy/light headed, than stop the exercise right away. It's something that will take adapting to, by the body. And would suggest doing the squats in a PR/cage/safety rack, spotters/etc, if problems arise. Good luck.
Just to note: 400lb + have been used by men, in the 20 reps breathing squat, over the years. Had a few high school and college athletes manage that , quite well. If nothing else, it will build major stamina (endurance + strength). Can also use clean, Hi-pulls, DL's, SLDL, etc. But , in truth, nothing beats the squat for this type of training.