Bioballs that float halfway out of the water are incredibly inefficient at housing aerobic bacteria. IMO
I would take the side of the LR rubble. If you can find some places, they will allow you to take a lot of rubble from their bins of LR for cheapcheapcheap. But if you're only option is to buy LR and break it, I would much rather go with the bioballs for simplicity and price reasons.
It is your choice, you have to weigh the pros and cons. As said before, bioballs are easy to clean and LRR is not. One advantage to LRR though, is that it can house some anaerobic bacteria that is able to convert nitrates to nitrogen and oxygen. Which is something that bioballs can't do.