Like anything else alot of the results will be determined by the care and use of the trailer, In Michigan, if you are going to haul all winter and don't have an easy way of cleaning the bottom of the trailer, then you will have a rust problem. Some steel framed trailers are rusting on the lot when they are new, some others seem to last a while longer before they have noticeable problems. If you are going to keep the trailer outside on dirt that will create more of a problem that if kept inside on concrete.

As far as the Merhow, they make alot of different style trailers from steel framed all the way to all auminums. But are generally considered as a lower end trailer, having said that, they can also be the perfect trailer for some folks needs.

The issue isn't with the aluminum skin, it involves the steel frame. Galvaneal, galvalume and galvanizing are all treatments used in the manufacturing of steel to reduce the effects of oxidation. Some trailers only have a bare steel frame, that may be covered with an under coating. Where you live and its environment, will have a direct affect on how long your trailer will survive.

Just as all aluminum and all steel trailers are not created equal, so too, neither are the hybrids. How the two dissimilar metals are attached and separated, will determine if any electrolysis or galvanic reaction will occur.

With one hundred and fifty manufacturers building trailers, and everyone of them claiming to be the best, the only way to determine their suitability in your environment is to poll the owners who live in your area.

I can tell you that "an all steel trailer is a poor choice", and that would be true for western PA. If you lived in western Texas, that would be an incorrect statement. "All aluminum trailers crack and the roofs leak". This may be true for one brand or model, but when applied to all aluminum trailers, it has no veracity.

Hybrid construction is the same way. It has a market share because it is less expensive to build a steel frame than a comparable one in aluminum. There are companies that build an excellent trailer using quality materials and techniques, and there are those who do not. You will find the same thing in an all steel and all aluminum constructions.

When you visit the various manufactures' web sites and see a steel company bashing an aluminum construction, or the aluminum company discounting the steel manufacturing, it is all hype. Each one has it's proponents, because in the right location, each one works well.

Oxidation effects both steel and aluminum. One has a natural resistance to it, the other will suffer from it. Both work. You have to learn about the various manufacturer's products from the previous owners. That's the only way to be sure how they perform in a real world environment.

Gard.