FergIt's all personal preference about number and shape of the blades. The Trapper is the most popular Case knife model in my estimation, I think of it as the default Case knife. The Mini Trapper is just a smaller version. So if you are trying to get exposed to Case knives I think it is a good decision.
For my personal preference, I dislike multi-blade knives. It may be my OCD coming out but I don't like having to sharpen and maintain multiple blades, and my needs are general enough that one blade shape is enough for everything. So none of these would be my choice for that reason. But I suspect I am in the minority since most traditional folders are multi-blade.