From my experience, a rack works well if you play a bit of bike Tetris and I highly recommend buying some foam pipe lagging to clip around the frames and forks in areas where they might run to save any tears. I’ve also got the 4th bike adaptor too. For my kids' bikes. Have used the adapter on long trips to France as well as lots of local trips, and to transport a BBQ. The only downside is it’s quite bulky and heavy when off the car.