Just a word of caution...the A/C "upgrade" should be viewed with a bit of skepticism. While the Coleman NDQ may be a bit quieter than the standard Coleman 13.5k BTU you are also going up in capacity. This larger capacity unit is likely not required except for maybe the larger trailers (upcoming 23?). With an oversized unit you cool too quickly and don't properly dehumidify. That's a cold and clammy feeling versus cool and dry. As mentioned unless they are more efficient there will be difficulty running on the popular smaller wattage generators like the Honda EU2000/2200i if desired.
Regarding noise it does appear that the NDQ is a step in the right direction. This is from website postings from users and not-scientific but mfr's of loud A/C don't post noise values. Dometic Penquin units can be in the mid-60's to 70 dB on high cool which is similar to the standard Coleman unit. The Coleman NDQ appears to bring this down to around 60 dB on high cool. If you want to reduce noise another 10 dB from the Coleman NDQ you should consider the unit installed by Advanced RV which is a Houghton Belaire designed in Australia. You are talking dB level in the low to mid-50's on high. I think they will now ship these to other OEM's for installation.
https://www.escapeforum.org/forums/f40/21-ne-air-conditioner-17936.html#post338351
People may be tired of hearing it but I come at this with the perspective of an HVAC background and having installed probably the quietest and most versatile air-conditioning solution possible with a mini-split. 43 dB on high and 23 dB on low.