You can use low bar for your main work (5/3/1 sets and reps) and then use high bar for supplemental work (Widowmakers, BBB, BBS, SST or any other supplemental program. This means you dont have to drop one for the other, you can use them both.
Main work: 5s PRO with Low-bar squats
Supplemental: 1x15-20 @ FSL
Main work: PR sets with Low bar
Supp: 1x15-20 @ FSL
Make sure have separate Training Maxes for each. Test your TM for the lift you want to use.
You dont have to use both. you can use either hi bar or low for all around