Sounds good indeed to hear they are working on lower rpm and water cooled. I have Chinese Silent enclosed unit by another name that is essentially the same as the Aurora and it has served well so far. Just completed a 70 hour stint due to Isaac of which about 58-1/2 hours were non stop fueled on the go. (I know, I know, not supposed to do it, but be honest a lot of folks do it and just don't admit it.)
I am jazzed to hear about the lower rpm water cooled 2 cylinder option coming just hope it will not take them long to up the ante a bit to a higher watt rating more in the 8,000 continuous and maybe a 9,000 to 9,500 surge range. 5,500 continuous gets me by, but an extra 2,000 to 2,500 would give much comfort. All of this is on the hope that they stay relatively close to the current pricing level per Kw. Been wondering when they are going fill in the jump between the 5,500 and 12,000-15,000 units both in wattage and price.