Sounds too short for most fly fishing applications. I have a 6 foot, 1 weight rod for fishing very small streams. But for a general trout fly rod, you should be thinking of a 9 foot 5 weight. Fenwick used to make cross-over rods, meaning you could use them for fly or spin fishing. The rod in question may fall in this category.

As far as whether it is worth it, that depends on how much you value $19.95. Only you can answer that question.