So far so good. I've had it set up for a day or so. Tiny water bubbles collect inside the tubing, but nothing that could ruin the siphon action. And with plants constantly drinking water, it will be flowing... very slowly, but still flowing, so that might reduce the amount of air bubbles. It'll be nice to keep the water level constant all the time.
I guess one problem could happen when the water pump is working to feed water up to the Perlite bucket. The res water level drops about an inch or so when that happens. So if the RO water from the jug flows in to raise the level up, the res's water level could go up an inch higher than normal. That'll be interesting to watch, to see what happens. I don't want any overflows!