Im still learning , practicing on my controller (i hide bpm counters). I use waveforms just to set the cue , but occasionally im setting my cue by ear, just to get the idea. I think its usefull to learn to match by ear. Last weekend i went to my local dj store (im taking a course there), first time ive seen cdj’s but i did beatmatch the tracks OK. (not super perfect, but im still learning 😛 ). At the end of the day , the way i see it , it really doesnt matter how you do it , if you get the job done. But as a backup plan it is a good idea to learn to do it manually.