Kettlebell Training on Off Days

Real quick question. Would doing a 20 minute KB workout on off days be ok for conditioning if I am already doing a 3 day a week full-body routine?

I ask because I have access to a small cardio room with treadmills and spin bikes on my off days, which also has a few KBs ( I was thinking of using a 20kg KB). Or should I do a HIIT workout on a bike for 15-20 minutes instead for a bit of conditioning?

Thanks for the advice in advance.

What is your goal?

What programming are you doing on your lift days?

What would a KB conditioning workout look like for you?