Indoor practice balls

Just picked up a chipping net, but realized I have no clue what sort of balls to use with it.  I live in a large loft with hardwood floors, so real balls are out.

Anyone who practices chipping indoors, what do you use? Wiffle balls? Foam balls?

Doesn't the net catch the balls, meaning they don't hit the hard wood and you could use real balls?

I use BirdieBalls as practice balls, but those are decidedly for full swings outdoors, not chipping.  I came to those cause I've never like any of the other practice balls actually shaped like regular balls, and I imagine it would be hard to dial in the light touch and distance control with short little pitches and chips with the whiffle balls.

Are you just worried about bouncing the balls off the hard wood when you miss the net?  Maybe just consider it extra motivation to get accurate fast?!  :-P

I chip inside with the foam Almost Golf balls all the time. For a while I was chipping 140 balls into the net every day before work. My short improved significantly with the practice.

I use the AlmostGolf balls too.  I chip inside the house with them nightly.  I even hit flops up into my loft/bedroom!  And no, you won't be nuts using them.  If you start rocketing balls over the green on the course, you have other problems to address.