Having owned this very unit now for a few years, I can tell you that it's a great floorplan, particularly if you have kids.
My 2021 has the half top bunk in back, queen up front with cabinets and an absorption fridge.
If I had to do it over, I'd go for the twins up front. Why? Getting around that queen is not as simple as it looks. More room to change with twins, more exterior storage access. Also the twins get two front closets which were nixed when they removed the queen closets to allow a real front pano window.
If you boondock, the
12v compressor fridge will be in issue. 2024 and newer has a $5k option for 400AH of lithium batteries and more solar, but for the solar to work, you gotta be in sunlight. When I boondock, in mostly rustic campgrounds, there are trees, lots of them, reducing or outright limiting the solar power assistance. With the new rear full top bunk, to me the lower bunk seems a bit like a coffin, and the lack of any operating rear window as well as one HUGE window in the bathroom didn't overly impress me, but as has been pointed out, trade offs (again 2023 or 4 that rear bunk and bathroom window thing started).
This trailer has a massively heavy hitch weight. I weighed mine and came in just under 1100lbs partially loaded and I do tend to pack the trailer conservatively/lightly- truck not so much, but trailer for sure-, so make sure you have a TV that can handle the 8800lb trailer and the 1100lb hitch weight. It all depends how you load it up. I've hear some around 1000lbs and some at 1200lbs.
Get the 3" lift done and don't look back. I just got back from a 4000 mile round trip up to Banff, and back down stopping at Glacier and TR National Park. I can't begin to tell you how many times, even as careful as I could be how that lift kit on this trailer made the difference between a butt drag and a clear pass. In my opinion, with this trailer or any trailer 30' or longer, this shouldn't even be an option. Don't let the naysayers convince you otherwise, there are no ill effects I found other than maybe needed a few extra lynx leveler lego pads for the stabilizer jacks.
Macerator toilet- I think this was added a few years after the 30FB bunk arrived sometime around 2005ish. Reason being, the unit can sleep 6 comfortably and up to 8 sort of packed in (storage is a different story with that many, but...). The 18 gallon tank that was under the toilet would fill way too quickly with a lot of folks, so Airstream appears to have solved that by putting a bigger black tank in the trailer. Problem was, could not fit a larger tank back there in the same area without serious problems, so the Macerator toilet came to be so they could put a larger black tank in further away from the toilet proper and poof, the old bomb dropper toilet was gone and replaced with a piped Macerator toilet. It does work, but it does use a heck of a lot more water.
Like nearly all newer Airsreams, they have the Girard on-demand water heater. If you boondock, taking a navy shower can be difficult as the water heater has a high flow to activate and then if you shut it off to lather up, you get about 15-20 seconds of residual hot water, then it goes cold again as it did when you first started. This wastes a ton of water, but is really only a concern if you boondock. Most folk replace that water heater with a Truma and solved most problems as I've described.
If you get a preowned unit built prior to mid 2023, pay particular attention to the front sides of the front storage door behind the LP tanks. These units are notorious for front end separation. Dimples on either side of the utility door, many popped rivets that hold the door to the skin are a tell tale sign the unit has or is starting to get FES. After I think mid 2023, they came up with a fix, but out of warranty, if the skin is not cracked, can be about $1700. If the exterior skin is cracked, plan on significantly more. This is not unique to the 30' bunk, but most larger units with front storage...but given how heavy the front end can be, and the weight distribution can really take its toll on this unit if not properly secured.
Bottom line, it's a great floorplan and those are my observations. I would buy another, or even a new one- even with the limitations and dislikes I mentioned. Also fully agree, 3/4 is the minimum you should have for this trailer and having just gotten back from some serious mountain driving, diesel would have been far better. My gasser did it, but it was in 1st gear at 5-7% grades fighting to keep at 35-40mph. If you only travel the flatlands, basic 3/4 ton gasser would be fine. Most 1/2 tons don't have the payload for something like this...most, not all.