So I've received two pms asking about this - so I figured I'd answer here instead. Due to a mistake on my part for the last month or so andropilot has been falling back to the much slower open source serial library. This was not my intent - it should have been using the faster (ftdi device) vendor library. 1.9.02 fixed this.
So paramter downloads (and all other communication) for older phones should be about 6x faster now - nothing is failing. (I've also just released this version to GA)