RE: Rubber Bands or Bolts?
I don't know who told you that rubber bands are bad for acrobatics, but they are wrong.
I use rubber bands on all my combat planes. They are high or shoulder wing planes (just for convience), so the bands are holding on the wing. We pull more Gs on a regular basis than just about anyone else out there. Maybe the Pylon guys are in the same range as we are in combat. But you can be sure that we pull many more Gs than your trainer would even think of. If you're going to really wring it out, you can add an extra couple of bands, but that's not always necessary. Just keep in mind that too many rubber bands will mean the wing can't shift when it needs to.
If you don't have enough bands on the plane, or the dowls are set too close, it's possible to get the wing to lift a little in a high G pull.
I will say that rubber bands are a royal pain, and once you get to the point that you aren't worried about dorking up a landing or takeoff, it's nice to ditch the rubber bands.