As mentioned, the best one is the floor plan that fits your needs.
In general, Forest River has had good reviews. All of the manufacturers build a bad one, occassionally. I have had four travel trailers. Two, including the current one, have been Flagstaff's (by Forest River).
The key is how they are maintained. An entry level unit, that is well maintained, will last longer than a high end unit that is neglected.
When you drag these things down the road, at 60+ MPH, things are going to come apart, doesn't matter who built it.