There’s no reason any website or browser should require the Java plugin. It was simply laziness on Medtronic’s part. Luckily, enough people yelled loud enough that they finally have updated their site so that that plugin is no longer needed.
I’ve been using the 670g in auto mode for 4.5 months now. I find it much better than manual mode, but not nearly as good as it could be. The internal code is buggy but hopefully there will be updates.