I bought a 2010 used Aliner in 2014, from a couple who'd upgraded to a small Airstream, and I kept it for 1 year. I missed being able to stop and quickly jump into the trailer for a snack, a bathroom break, a lunch, etc. The door didn't align well. Several little things went wrong in that year, like the curbside window not closing right. All storage is down low, so be prepared to bend over... a lot. Storage is limited, too; I know one couple who carried bins of stuff in their vehicle, and brought the bins into the Aliner every time they set up camp. Also I got a bit of a sore back from doing dishes because the counter is so low, even though I'm only 5'8" (mine wasn't a high wall, which might make a difference).
I think I got $500 less than what I paid, after a year of use.