Bob,
I don't know much about the other brands you listed, but I can vouch for the quality of Holiday Rambler (HR). The reason is in the construction. Among other features, HR uses a welded aluminum frame, and excellent insulation in the walls.
We have owned two HR's. The first was our home for a year and a half and was still in great shape (somewhat worn and dirty but structurally sound) after being pulled from Indiana to Rhode Island to Florida to Mississippi to Texas to California. We put about 4000-5000 miles on that trailer and lived in it full time. I wish I could buy it back today. I'll bet it's still in good shape.
We currently own our second HR. We bought this one used about a year ago. It has about 100,000 miles on it (owned by professional dog show handlers), and it is also still sound. I agree with Dshelton and Andy. Buy used, not new. We got our 5- year-old HR for less than half the price of a new unit. We spent about $1500-2000 on fix-up items. They were mostly cosmetic, but felt we could afford it considering the savings on the trailer.
Dshelton also said that Carriage is a good brand. I have no personal experience, but the RV repair guys who have fixed up our HR also said that Carriage units are well made.
I disagree with Big Mike. You won't necessarily love whatever you buy. Trailers are a bit like boats. You buy one, then you find out what you really should have bought. I thought I wanted a fifth-wheel until I actually had to use one for a few years. You lose the use of your truck bed with a fifth-wheel, and can't tow one with a short bed truck unless you buy a very expensive hitch. They are usually big and heavy also, but I'll admit they tow like a dream — very stable. A well-loaded travel trailer will also tow well. Just keep plenty of weight on the tongue.
I also thought I wanted slide-outs until I used them. Two disadvantages: First, they add weight to the trailer. Second, when you are traveling and want to stop for a sandwich the retracted slide-out often interferes with the use of the trailer. Do you really want to extend your slide-out at every rest stop?
I have used trailers with fiberglass sides and aluminum sides. I don't really have a preference, although the fiberglass seems to come on the up-scale trailers. They both do the job well.
Another feature not mentioned yet is a generator. I have used trailers with and without generators and would really like one in our current HR. I'll have to settle for carrying one in the pickup. You can run almost anything in your trailer on LP or batteries, EXCEPT for the air conditioning. For that you need AC power. If you can't plug in, a generator is the most practical way to get it. You will have to decide how you expect to use the trailer and whether or not a generator is a deal-breaker. We bought our current HR without one, and it has worked out alright so far.
I agree with Oilbrnr. Airstream is quite probably the top brand in travel trailers. They certainly retain their value better than almost everything else. I don't like the rounded backs in the storage compartments inside. That's why we bought our first HR thirty years ago.
Features sell trailers to first-time buyers. Quality sells to second-timers. Poor trailers are REALLY poor. It's not like the difference between a Chevy and a Mercedes. Both of those cars will do the job. The poorer trailer brands won't even tow. Axles will bend, brakes will break, roofs will leak. Stick to quality. Even if you don't like the features on the quality trailer you buy, at least you will own some value for a trade-in on the trailer you want to get.
If it's possible, come to Elkhart, IN. Trailer Mecca. You can learn more about different brands in a week in Elkhart than you can in six months anywhere else. You can see them all, talk to the hitch and accessory installers about brands (most of them don't have a trailer to sell you), and even tour several factories.
If I were shopping for a trailer again, the brands I would consider are Holiday Rambler, Airstream, and Newmar. The more I learn about the Newmar products (Kountry Aire, Mountain Aire, etc. ) the more I like them.
Some web sites:
www.holidayrambler.com
www.newmarcorp.com
www.airstream.com
Happy hunting.
Loren