I bought a 2013 Aliner Scout and just replaced it with a 2016 Aliner Expedition. It was $21k, so they're not cheap. Nor is the construction quality anything to brag about, but that seems to be the case with most popups, and even travel trailers.
Having said that, I love it for it's ease of towing and popping up. It's perfect for me as only I use it. As is often said about most camping units, modifying it is almost always necessary to create the comforts and conveniences that seem to be in short supply, regardless of what popup or travel trailer you buy.
I could have bought a pretty decent travel trailer for what I paid for this, but the lower tow profile was a big selling point for me as well.